Aviation Classics 9 F-86 Sabre preview

Cockpit of a restored F-86F. Frank B. Mormillo

Contents 6 Friends

51 Jock Maitland - RAF Sabre pilot

7 Swept wing technology

56 The Barnes Incident and the 60th FIS Aerobatic Team

10 The XP-86, F-86A and P-86B 20 Supersonic?

23 Day fighters – The F86-E and F 34 Over the Yalu

IN MEMORIAM This issue of Aviation Classics is respectfully dedicated to the memory of aviation researcher, writer and artist Michael A. Fox, 2 October 1961 to 7 January 2011. His friends remember and miss him and the aviation world is a lesser place for his passing.

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64 The Heavyweights: F-86C, F-86D and F86L 76 Last of the Sport Models – F-86H 84 The export models and overseas production

92 Sharkmouth Sabres 94 Flying (and ejecting from) the aircraft 100 The North American FJ Fury 115 The 100th Anniversary of Naval Aviation

Editor:

Tim Callaway and Duncan Curtis editor@aviationclassics.co.uk Dan Savage Duncan Curtis, Norm DeWitt, Douglas C. Dildy, Keith Draycott, Michael A. Fox, Julian Humphries, Frank B. Mormillo, David G. Powers, François Prins, Constance Redgrave, Clive Rowley

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122 Oddities

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126 Survivors

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ISBN No 978-1-906167-38-7

Above: The F-86F of the Planes of Fame Air Museum is seen here in flight over Chino. Frank B. Mormillo Cover: Michael Dorn, the famous actor who played Mr Worf in Star Trek is seen here flying his Sabre over Southern California’s San Gabriel mountains.This aircraft was built as a Canadair Sabre Mk.6 and painted to represent an F-86E of the California Air National Guard.

Subsequently the aircraft was owned by astronaut Frank Borman before being bought by Comanche Fighters.

Frank B. Mormillo

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North American F-86 Sabre 5

The Planes of Fame Air Museums F-86 and MiG-15 in a Korean War re-enactment at the 2009 County of San Bernadino Planes of Fame Airshow. Frank B. Mormillo

Friends A

s I began my second issue as editor, I found myself dealing with an aircraft I thought I knew well, the F-86 Sabre. As time went on however, more and more came to light that I was unsure of or found questionable despite the oftdocumented history of the type. This is where I really began to understand the power of friends.

Doug Dildy, an ex-F-15 driver and a tremendous aviation historian of note, introduced me to Dave Powers. Doug was writing the excellent Korean War section of the magazine and suggested Dave as the man to cover the naval variants of the Fury.

As a docent at the National Naval Aviation Museum, Dave was well placed to research the types in depth, and did an astounding job as you will see. Of course since we were covering a Naval topic, Norm DeWitt’s suggestion of a piece on the 100th Anniversary of Naval Aviation was another great idea. He and Keith Draycott have produced an excellent piece on the celebrations.

Doug also suggested that the man to write the rest of the issue was Duncan Curtis.

Thanks to Doug’s suggestion, this issue of Aviation Classics is as good as it is.

Every now and then you meet someone who is simply the world expert on a given subject. This is Duncan Curtis, and his subject is most definitely the F-86. Duncan served for 24 years in the RAF as an airframe/engine technician, initially with search and rescue Wessex helicopters and then via Pumas in Central America to seven years doing airframe repairs on the C-130 Hercules.

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Since 2005 Duncan has worked as a technical author for Airbus. His interest in the F-86 began in 1974 when his curiosity was sparked by a photograph of Ben Hall’s F86A in Aviation News magazine. Since then he has written six books on the subject and contributed a number of further magazine articles. He also runs a dedicated F-86 website, http://f-86.tripod.com.

Basically, if someone is restoring an F-86 anywhere in the world, Duncan is probably involved in some way. Sitting in his home one day, a question of detail arose, so he disappeared into his prodigious library. He returned with the official air force manual of the type we were discussing and examined the engineering drawings therein. “Where on earth did you get that?” said I. “Oh, I have most of them for most models” said he!

Nearly the whole magazine has passed before his eyes, so it is only fair to say Duncan Curtis is the co-editor of the F-86 issue, as he has contributed far more than I. Thanks Duncan, good job!

Keeping on the subject of friends, this issue also introduces the work of Adam Tooby, a renowned artist who will be familiar to many aviation enthusiasts because of his work on the Airfix models boxes. As an avid Airfix collector myself, I was delighted when Adam contacted me asking if he could help with illustrating the pages of Aviation Classics.

From now on, each issue will feature two double page artworks from Adam, exclusive to the magazine. This month he has chosen to depict Maj George Davis of the 334 FIS, 4th FIW on the 30 November 1951. On this day, one of the largest air battles of the Korean War took place, with F-86s

Duncan Curtis intercepting a force of 12 Tu-2 bombers with La-11 escorts and a MiG-15 CAP. George Davis shot down 3 Tu-2s and 1 MiG-15 and damaged another Tu-2 in F-86A 49-1184.

Davis shot down the MiG after he returned to the fray to help his room-mate, Capt Raymond Barton, who, as Barton put it himself, “had started to collect more MiGs, who seemed to be more than a little irritated.” Davis shot one of the gaggle of MiGs behind Barton down, and both returned safely to Kimpo Air Base.

The other artwork from Adam is part of our tribute to the late Michael Fox. It is the 60th FIS Aerobatic Team in formation, their classic diamond.

Michael’s sudden death in January occured just after he had completed his article on the 60th FIS, and shocked us all, as Doug Dildy, Duncan Curtis and I had all been in touch with him. Everyone at Aviation Classics sends their heartfelt condolences to Michael’s family, and thanks to his brother, John, for his support.

It is hoped that Michael’s book on Sabre Aerobatic Teams of the World may yet be completed, as his artwork for it and research on it is mostly complete.

They say that friends only die if we allow them to be forgotten. I hope that this issue of Aviation Classics helps the memory of Michael to live on.

All best, Tim Callaway Editor

Swept wing technology It was mainly German aeronautical engineers who pioneered the swept wing for aircraft, says François Prins.

W

e tend to think that the swept wing is something that only came about with the advent of jet aeroplanes, but in reality it was being experimented with by several aircraft designers from the earliest days of manned flight.

While powered aircraft kept to a simple design of fairly square wings with little or no sweep, glider enthusiasts were going further and adding sweep to the wings of their craft as the searched for better flight characteristics that suited a machine dependent on the wind.

In Britain, José Weiss experimented with hundreds of model gliders before making a full-size tail-less glider with swept wings. It flew successfully in 1908, so he built another but this time powered by 12-hp Anzani engine driving two propellers. During the winter of 1908-09 it was tested at an airfield in Essex but, until some modifications were carried out, refused to leave the ground.

Another pioneer of the swept wing theory was John William Dunne; he experimented with models before building a full-size tailless glider with sharply swept back wings in late 1905. Encouraged by the success of the glider, Dunne built a powered aircraft which, after some initial problems, made several successful flights. Dunne built variants of the aircraft and one crossed the English Channel in 1913 to be demonstrated in France.

With the coming of war Dunne ceased work on his series of tail-less aircraft.

However, many of his ideas and designs were

One of Alexander Lippisch’s futuristic looking craft for the Luftwaffe was to be the Lippisch 13a delta wing fighter.

This, model test glider – Lippisch DM-1 – was under construction to test flight characteristics.

adapted by others including Westland Aircraft. They built a series of tail-less gliders and powered aircraft which culminated with the successful Pterodactyl IV of 1931. It was not put into production and the swept wing theory was not taken up in Britain by any of the leading aircraft designers and manufacturers of the day.

GERMAN EXPERIMENTS

The Versailles Treaty of 1919 forbade Germany to design and produce military aircraft. However, there was no mention of gliders and light sporting types, so the engineers who had worked on aircraft during World War One turned their talents to powerless flight. Gliding became a fastgrowing sport and competitions held in Germany attracted participants from all over the world; it was seen as harmless and fun, but the data gathered from gliders could be used by the designers for other aeronautical applications.

One of the many glider designers was Alexander Lippisch; he had worked with Dornier in the latter stages of World War One and was one of many men who found themselves unemployed after 1918. Lippisch applied for a post as an aeronautical engineer with Fritz Schweizer who wanted to enter a glider for the 1921 Rhön competition. Lippisch built the glider and soon afterwards joined forces with another glider builder, Gottlob Espenlaub. They continued their experiments with tail-less craft and in 1927 Lippisch produced the first of his Stoch gliders, which would later be developed to take power units.

These were developed into his Delta design series, which would eventually lead him towards the Messerschmitt Me 163 concept.

While Lippisch was experimenting with the Delta aircraft, the Horten brothers – Walter and Reimar – were building small glider models based on the Lippisch’s Delta tail-less design, but taking it further as a

Alexander Lippisch photographed just after World War Two in his office. He holds a model of the proposed Lippisch LP-13a high-speed, ram-jet delta fighter. flying wing with the pilot and equipment housed almost entirely in the wing. They built and test flew large models that soon attracted the notice of the Deutsche Versuchsanstalt fur Luftfahrt (DVL) – the official German aircraft test organisation – who invited the Horten brothers to demonstrate a glider at an air show in Hangelar in June 1934. The DVL agreed to pay all expenses and the aircraft was shown to a large audience that included many influential members of the ruling Nazi party and the new Luftwaffe.

When Reimar returned home to Bonn he started work on a second aircraft; this was for a glider, but he also had plans to build a powered version. Both Lippisch and the Horten brothers continued their experiments with tail-less and/or flying wings throughout the 1930s. The Deutsches Forschunginstitut fur Segelflug (DFS), the German Research Institute for gliders, but also covertly for powered aircraft, gave Lippisch the opportunity to build a glider that could be easily converted to take an engine.

Right: Gliding was popular in Germany between the two world wars and gave young designers valuable data on flight which would hold them in good stead later.

North American F-86 Sabre 7

In 1938, Lippisch joined Messerschmitt AG at Augsburg; he now had the opportunity to develop his tail-less aircraft for one of the largest aircraft manufacturers in Europe.

Some of his former colleagues from the DFS joined him at Messerschmitt and brought all his drawings and calculations for the rocket fighter that he had been working on before joining Messerschmitt.

The glider prototypes – DFS194 V1 and V2 – that Lippisch had built were also transferred to Augsburg and the proposed powered aircraft was designated Me163 in the Messerschmitt catalogue.

Early in 1939, in order to gain first hand knowledge of the Walter rocket motor that was scheduled to power the Me163, the DFS194 V1 was quickly modified so that the engine could be fitted. The aircraft was flown as a glider from Augsburg before being taken to the test centre at Peenemunde for powered trials. However, the outbreak of war halted work and the first powered flight was delayed until the summer of 1940. Trials with the light and very fast DFS194 encouraged the Luftwaffe high command and work proceeded on the first prototype Me163; this

A Messerschmitt Me163B captured by the allies and taken to the USA for testing.

Only one allied jet fighter saw action during World War Two, the Gloster Meteor shows how different the thinking was when it came to high-speed jet flight. was flown from Peenemunde on 13 August 1941 for the first time and during trials it reached a top speed of 515mph (830kph).

Meanwhile, the Horten brothers had joined the Luftwaffe and the special organisation known as Sonderkommando 9, where they were allocated the task of developing their flying wing concept. Work proceeded and was developed by the Gothaer Waggonfabrik AG – better known as Gotha aircraft – during the early 1940s. By 1942 work had commenced on the Horten Ho IX V1 prototype to be powered by two BMW 003A-1 axial flow turbojets. However, problems were encountered by the build-team at Gottingen when they found that the BMW engines were larger in diameter than originally planned. The first prototype was thus finished and flown as a glider in the summer of 1944.

ROCKET AND JET POWER

This image shows the prototype Messerschmitt Me163 (left) with a production Me 163B for comparison.

The fast Me163B was a dangerous aircraft to fly and the fuels when mixed were highly volatile, consequently a special suit was designed for the pilot to protect him from any spillage.

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By this time the Messerschmitt Me262 jet fighter and the Me163 rocket interceptor had both entered Luftwaffe service. When the first powered Ho IX flew, now powered by Jumo 004B-1 turbojets, it was behind schedule. The test started well but two hours into the flight one of the Jumo engines caught fire and the pilot had to make an emergency single-engine landing. Unfortunately, the Ho IX V2 was destroyed in the fire.

However, the aircraft showed promise and was ordered into production as Gotha Go229; the first pre-production example Go229 V3 was being made ready for flight when the Gotha plant at Friedrichsroda was captured and occupied by the advancing American army. Naturally, the Go229s that had been completed and those in-build were seized, as were other German advanced concepts at other locations.

What the Allies discovered was amazing, they knew that the Germans had been working on rocket and jet propulsion but they had not expected the sheer diversity of aircraft designs and concepts. One of the Messerschmitt aircraft they captured was powered by a single turbojet with a nose intake, sharply swept back wings, a high tail and cannon armament in the nose. Designated P.1101, the aircraft had wing sweep back that

could be varied in flight from 20 degrees to 60 degrees. The P.1101 had been selected as the future fighter for the Luftwaffe.

Also discovered by the advancing troops was a similar design to the P.1101, which had been worked on quite independently by Kurt Tank of Focke-Wulf. Tank was not only an accomplished aeronautical engineer but also a fine test pilot; he insisted on flying any design he had been involved in. Tank’s Ta183 had been ordered early in 1945 for flight in May or June that year. Work was well-advanced when British troops captured Focke-Wulf at Bad Eilsen where Tank and his team were based.

The Ta183 had not been built, unlike the P.1101 and all that could be seen were some scale models and hundreds of drawings. Tank was interrogated but did not give much away to those who were questioning him and he made no mention of the Ta183.

This aircraft was to have its wings swept back 40 degrees and mounted mid-fuselage; the tail-fin was raked back 60 degrees and the swept back tailplane was mounted on the top of the fin. Tank’s calculations showed that the Ta183, powered by a Heinkel-Hirth HeS 011 turbojet, could exceed 600mph (965kph) and in combat could cause havoc with the highflying USAF bombers which were eluding the Me 262s. Further, the Ta183 was to be armed with four 30mm MK108 cannons which would be more than a match for the guns carried by any allied aircraft of the time.

Tank had other variations of the Ta183 planned and each was more advanced than the preceding example.

The British and the Americans were excited by what they found as they advanced through Germany; the sheer scale of jet and rocket technology was far beyond what they expected and even further removed from their own researches. In the UK and the US jet aircraft were being designed and built but none were as advanced as the Ta183 and P.1101 or the Me163 variants. The partially complete P.1101 was taken back to the US and handed over to the Bell Aircraft Corporation. They used the basis of the design for the X-5 which first flew in June 1951. There are striking similarities between the two aircraft but in essence the Bell X-5 was a totally new aeroplane.

The two Horten brothers – Walter (left) and Reimar with three of their flying wing gliders in the background. Captured drawings and a partially completed Gotha Go229 were taken back to the USA and resulted in the Northrop Flying Wing.

POSTWAR BOOST

The Soviets had lagged behind in jet technology until they were given a boost by the new Labour government of Britain with an outright gift of several Rolls-Royce Nene turbojets as well as information and drawings. Their own spy network had also gathered allied technology that went towards developing advanced aircraft within the Soviet Union. Their advancing armies captured various German design and test facilities along with the engineers and scientists working at the locations.

Tank’s Ta183 may have been gathered up by the British but the Russians found a full set of plans of the aircraft, along with several other advanced aircraft designs, at the Air Ministry building in Berlin. They now had the technology for a high-performance jet interceptor fighter. These microfilm plans were rushed to Moscow and pored over by Russian aeronautical engineers. There is little doubt that the Mikoyan-Gurevich (MiG) design bureau benefited from the plans.

Some sources state that MiG built and flew copies of the Ta183 design, which were developed and adapted as required. Certainly the resulting MiG-15 owes a debt to the Ta183 as does the North American F-86 Sabre which had started life with straight wings but soon gained a distinctive and more efficient swept wing that was firmly based on the captured German technology that found its way to the States.

Sweden went one better and built the Saab J29, which looks more like the Ta183 than either the MiG-15 or F-86.

Tank himself went on to other things including the building of the Pulqui jet fighter for General Peron in Argentina. Although the aircraft flew it did not enter production, but it bears a remarkable resemblance to one of the proposed variations of Ta183. Britain, America and Russia all benefited from the captured German swept-wing information which enabled the allies to make rapid strides which otherwise may have taken several years. ■ Words: Francois Prins

The F-86 Sabre cockpit is well laid out and spacious for a single seat fighter.

Unlike the Sabre cockpit the MiG-15 is cramped and purely functional, there are no frills, it is a workplace.

Kurt Tank designed the Pulqui II for the Argentine Air Force, but it never entered production. He based the design on the Ta 183 which was due for build when the war in Europe ended.

North American F-86 Sabre 9

The XP-86, F-86A and P-86B Though it was not flown until 1947, the Sabre can be traced back to North American Aviation (NAA) project NA-134, an aircraft originally drawn up for the US Navy. The earliest known NAA drawing for this ‘Jet-Powered Shipboard Fighter’ is dated 13 October 1944 and this machine was planned to be capable of supporting the impending May 1946 invasion of Japan. NA-134 was soon approved for production as the FJ-1 Fur y.

M

eanwhile, the US Army Air Force (USAAF) had issued a design request for a medium-range day fighter to fulfil the escort fighter and fighter-bomber missions.

A top speed of 600 mph was stipulated and, on 22 November 1944, NAA put forward its RD-1265 design study for a version of the NA-134 to meet the USAAF requirement.

The aircraft was assigned the NAA model number NA-140 and its design team was led

by John ‘Lee’ Atwood. Other key members were Ed Horkey as chief aerodynamicist, Tony Weissenberger as project engineer and Art C Patch as his assistant.

The NA-140 was designed around the General Electric (later Allison) J35 axial-flow turbojet and was able to employ a thinner wing and slimmer fuselage than the Navy design. Armament for both aircraft would be six .50-calibre machine guns arranged on either side of the nose intake. Top speed was one of the primary characteristics on which the USAAF was most insistent, but NAA engineers already knew the early concept of the NA-140 fell almost 20mph short of the 600mph goal and this was proven through wind-tunnel testing and mathematical projections: at a gross weight of 11,500lb, the design would only be capable of reaching 574mph at sea level.

Despite this shortcoming the USAAF authorised Letter Contract AC-11114 on 18 May 1945 to cover three prototype aircraft.

These machines were designated as XP-86 ‘Experimental Pursuit’ types and would be built to accept two versions of the J35 engine: the Chevrolet-built J35-C3 or the J35-A5 assembled by Allison. USAAF serial numbers 45-59597 to 45-59599 were assigned to the three prototypes.

It was at this point that considerable amounts of captured German research documentation began to fall into allied hands, and in the United States Air Materiel Command began to assimilate this data and disseminate it to the aircraft industry.

Initial NAA model of the NA140, circa 1945. Note the ‘140’ signifier at bottom right. NAA 10 aviationclassics.co.uk

In fact NAA had a head start on most of its competitors because Horkey had learnt of the data through George Scharier of Boeing.

Scharier was one of a small number of engineers who had travelled to Germany at the end of the war. In addition to the data, as World War II drew to a close many German scientists started to work on American research and development projects and their expertise in swept-wing design was put to good use.

As an example of Germany’s progress into high-speed research, the Luftwaffe had already put two swept-wing fighters (the Messerschmitt Me 163 and Me 262) into operational service before the end of the war. In particular, the Me 262 was produced in large numbers, and featured a 15-degree wing sweep in its design. More importantly, the designers of this machine had largely solved the low-speed stability problems of its swept wing by installing automatically-opening leading edge slats.

These airfoil-shaped devices were held shut at high speed by aerodynamic forces, but extended at low speeds to increase the effective chord of the wing and thus increase lift.

Mindful of this new data, and despite USAAF approval of the straight-winged wooden mock-up, NAA engineers working on the program now proposed a swept-back wing for the NA-140. Key among the features included in the proposed redesign would be the adoption of leading-edge slats, and this would transform the aircraft into a practical fighter with a transonic capability but with good low-speed performance.

The swept-wing idea was first mooted in June 1945 and a series of NAA-funded wind tunnel tests was begun to assess the qualities of this new proposal. On 1 November 1945 the decision was made to scrap the straightwing design and go with the swept-wing XP-86 instead. The USAAF accepted that time would be lost as a result but was willing to make the sacrifice knowing that massive performance gains would result.

In the event, the prototype FJ-1 took to the air on 27 November 1946 and the first XP-86 flew nearly a full year later. By October 1946 a 5:1 aspect ratio wing had been decided upon, with a 37.12ft span and

swept tail surfaces. Further wind tunnel work and refinement brought the production wing’s aspect ratio to 4.79:1, with a sweepback of 35 degrees, and a thickness/chord ratio of 11 per cent at the root and 10 per cent at the tip.

Further investigation now revealed that the rearwards-opening concertina-type speed brakes planned for the XP-86 would be unsuitable, notably because they would fail in the ‘open’ position with a loss of hydraulic power. Wind tunnel tests eventually settled upon a front-hinged panel on each side of the rear fuselage, but the USAAF did not approve this version until September 1947 and as a result the No.1 XP-86 still had the ‘concertina’-type speed brakes fitted for its initial flight testing. They would be deactivated for flight testing.

On 20 December 1946, Letter Contract AC16013 was approved for 33 production P-86As, along with 190 P-86Bs (detailed elsewhere). ➤

Top: This view of the Muroc North Base (where XP-86 Phase II testing was conducted) shows the 2,000-yard runway at rear.The dry lake extends towards the bottom (south) and right (east) side of the photograph and was flooded during the winter of 1947/8. Later, a number of other Sabre flight test programmes were housed at the North Base, and centred around Building 4505, the hangar at bottom right. Courtesy of the Air Force Flight Test Center History Office Above: Two of North American’s postwar success stories in flight over Muroc in 1947: the XB-45 (rear) and the XP-86.The XB-45 bomber flew for the first time on 17 March 1947 and went into production as the B-45 Tornado. Courtesy of the Air Force Flight Test Center History Office North American F-86 Sabre 11

North American initially had proposed these conformal-type external fuel tanks for the Sabre (seen on the No.1 XP-86 at Muroc), but they were never taken up for production. Continued problems with buffet from the tank/wing interface led to a lot of subsequent testing, though in general the XP-86s did not carry external fuel tanks. NAA These aircraft would be constructed at NAA’s Inglewood, Los Angeles plant. Air Force officials decided that no service test aircraft were needed other than the three prototypes and so there were never any ‘YP-86’ aircraft.

FLIGHT TESTING THE XP-86 – PHASE I

The No.1 XP-86 was officially handed over to Flight Test on 8 August of 1947. The new NAA fighter was given the ‘PU-’ buzz number prefix (which would also apply to production aircraft) and so the prototype became ‘PU597’. The aircraft was disassembled, put on trucks and driven to the South Base area of Muroc Field (just south of the present-day Edwards AFB main site) and off-loaded on 11 September. George Welch would be NAA’s chosen pilot for the first flight.

On 1 October 1947, Welch took the XP-86 into the air for the first time and details of that day are covered elsewhere. Welch was generally happy with the aircraft and his main concern was that the aircraft did not have enough power – a problem that would be solved as soon as the J47 engine became

A poor-quality, but highly important photograph showing the first XF-86 as a static test aircraft at Frenchman’s Flat, Nevada on 8 May 1952.This is actually a still from cine camera footage as the first shock wave from ‘Encore’ blast of Operation UpshotKnothole sweeps through.‘Encore’ was a 27 kiloton air-dropped nuclear device and the aircraft survived it reasonably intact. Author’s collection 12 aviationclassics.co.uk

available. Initial concerns with high aileron breakout forces (the amount of effort required to move the control column from a static condition) were also aired by Welch, and ultimately a modified aileron bellcrank torque-tube with needle-roller bearings rectified this situation.

Flight number two did not take place until 9 October and as a result of the undercarriage problems encountered on the maiden flight, the gear was locked down. Flights three and four were completed on 14 October.

The pace of testing then began to hot up, with the United States Air Force (USAF) keeping a close eye on progress (the USAAF had become an independent air force on 18 September 1947). By 24 October seven flights had been completed, including the first familiarisation flights by Bob Chilton. Flights seven and eight had been the first to investigate engine and structural temperatures and confirmed expectations that temperatures would increase at higher speeds and lower altitudes. Many subsequent flights were devoted to resolving this issue and a further post-flight ground run after Flight 19 showed excessive hot air leaks from the engine air extraction manifold and the mid-frame seals between the engine mounting pads.

Continued problems with smooth slat operation led to the installation of spacer washers to take up end play and prevent a ‘racking’ action. The slats would be problematic throughout the early days and problems with binding rollers were eventually resolved with a revised slat track, more suitable lubrication and by joining the individual slat sections into one moveable surface. Aerodynamically, 597 had also been fitted with a 4inch wing trailing-edge extension to alleviate flow separation.

On 24 November the USAF and NAA issued simultaneous press releases indicating that the XP-86 had successfully completed initial flight tests. Interestingly, NAA’s version had been intended for release to the morning papers on Monday 17 November but for reasons unknown it was not until a week later that the public first heard of the XP-86’s existence.

Phase I testing was completed with Flight 32 by Welch on Friday 28 November. It was his third XP-86 flight of the day, all of which had comprised cooling runs at altitudes from 5,000 to 15,000 ft. At this point the XP-86 had flown 25hrs 2min. The airplane was then turned over to the USAF for Phase II evaluation tests, commencing Monday 1 December 1947.

Most of the 47-Fiscal Year F-86A-1s were used in the test role, and 47-610 was one of these. It was assigned initially to Edwards AFB for performance and stability testing before being transferred to Wright-Patterson AFB. It was then one of four F-86As at Wright-Patterson that were part of a short-lived aerobatic team known as the Acro Jests (sic). Large areas of the aircraft were painted in dayglo orange and outlined in black for this little-known episode. USAF via Dave Menard

All three XF-86s (redesignated as such from ‘XP-86’ on 1st June 1948) meet inflight for a final pose for the photographer, circa 1951. By this time all three aircraft had been fitted with F-86A-standard rear fuselages and handed over to the USAF.The second prototype is nearest the camera, with the first machine in the middle and the third XF-86 at rear. Author’s collection

PHASE II

In late November staff at NAA had contacted Col Al Boyd, chief of the USAF Flight Test Division at Wright Field, recommending that Phase II be delayed slightly.

Heavy rains were pounding the Mojave Desert around Muroc and portions of the lakebed had flooded. The pilot in charge of Phase II testing, Maj Ken Chilstrom, then inspected the area and recommended that Phase II be conducted from the self-contained facilities at Muroc’s North Base. NAA officials were concerned because of the extremely short 2,000-yard runway at North Base but the USAF pressed ahead and Maj Chilstrom taxied PU-597 out on 2 December to begin the second phase of the historic flight testing of the XP-86.

Phase II was short in duration, lasting just six days and comprising 11 flights for 10 hrs 17 min of flying time. Chilstrom made his final flight of Phase II on 7 December and declared himself highly pleased with the results, though the cabin pressurisation system was again inoperative and the oxygen system had trouble coping with such a condition.

Overall his impressions were full of praise and he later stated that: “My conclusion to the Phase II tests... was that the Air Force now had the very best jet fighter developed to this date, anywhere in the world.” ➤

CONSTRUCTION AND SYSTEMS In order to cope with the stresses of high-speed flight, the XP-86 design team had to face new challenges.The thinness of the aircraft’s wing effectively ruled out a conventional ‘rib and stringer’ design, and NAA’s head of structures Dick Schleicker came up with a revolutionary idea. He created a machine-milled double-skinned structure which featured integral top hat stiffeners from wingtip to the centre section.The wing skin was machined to taper in thickness from ¼-inch at the root to 0.032 inches at the tip, and this form of construction enabled strength requirements to be closely tailored in each area of the wing. Not only were major weight savings now possible but also the wing skins could be precisely machined to cope with the stresses of flight. A side effect of this design was that it was easier to accommodate fuel tanks inside the wing. Unfortunately US industry could not provide such machining and NAA was forced to develop the technology to build its new fighter. Specially-equipped milling machines with carbide-tipped fly-cutters (some of 12-inch diameter) were installed at the Los Angeles plant. Using these machines each skin took just over 45 minutes to produce.

To assist in engine removal, the whole rear fuselage could be removed from a point just aft of the wing.The engine exhausted under the swept tail surfaces, just forward of the trailing edge, so that a slight lip was present on the upper edge of the jet pipe.This aspect of the

design was said to eliminate snaking at high speeds as well as improving takeoff thrust. Surface finish also received close attention and flush-fitting rivets were installed throughout the external surfaces of the XP-86.These rivets were then milled fully flush after assembly.

From the start of XP-86 design, external fuel tankage was a high priority.

But with the change from straight to swept wings, it became difficult to mount such tanks on the wing tips and maintain a satisfactory centre of gravity.

Therefore, external fuel tanks were instead pylon-mounted on the wing as far inboard as practically possible, and this also resulted in the aircraft’s relatively narrow undercarriage track.

The cockpit of the XP-86 was fully pressurized, utilizing air from the engine’s 11th compressor stage at a rate of 10 lb. per minute at ‘full cool’ or 14 lb. per minute in the ‘full heat’ setting.Air was routed either through a turbine refrigeration unit for cold settings or bypassed for hot. During the aircraft’s test phase, considerable problems were experience in maintaining adequate canopy sealing, and for much of the time, the system was rendered inoperative.

Interestingly, the #1 XP-86 was the only one of the three prototypes that had an onboard fire-extinguisher system, and in fact was the only factoryproduced Sabre to have this feature. On all other F-86 aircraft, there was a fire detection system, but if the fire didn’t go out quickly and of its own accord, the only option was to eject.

North American F-86 Sabre 13

In fact the USAF was so pleased that it announced on 28 December 1947 the award of a further production contract for 225 P-86As.

PRODUCTION AND SERVICE – THE F-86A

Another poor-quality but important photograph, this time showing the little-known tests that NAA carried out to try and fit wingtip fuel tanks to the F-86A in early 1951.

The tanks were based on the standard 120-gallon combat tank and five different combinations of outward-canting and slight slat extension were trialled. None could resolve the centre of gravity and buffet issues of these ‘beaver-tail’ tanks.The aircraft is a late-model F-86A-5 s/n 49-1301. John Henderson

The XP-86 design went into production as the P-86A, and one of the most important differences between these two models was the introduction of the General Electric J47 as the P-86’s powerplant. The airspeed pitot probe was relocated on production P-86As – from the vertical fin to the inner surface of the engine intake. In addition, the one-piece nose gear door of the XP-86 was redesigned as a folding, two-piece item. The P-86A was also equipped with the standard armament fit – six .50-calibre machine guns with 300 rounds each. To preserve the streamlined form of the P-86, flush-fitting panels covered the gun muzzles. When the pilot fired the machine guns, these panels were opened automatically and closed after each burst.

Though they often proved temperamental in use, they were installed in all but the final production P-86As. Later, most surviving aircraft were modified to accept a more conventional open muzzle.

Other improvements on the production aircraft included the navigation lights, which had been installed in the trailing edge of the fin tip on the XP-86. These were relocated to the engine exhaust’s ‘pen nib’ fairing at the base of the vertical fin on the ‘A’ model.

Finally, the four separate slat sections of the prototypes were joined on each wing to act as one item on the production models.

Internally, many systems and cockpit changes were also made, and empty weight

47-617 was the aircraft that undertook cold weather testing in Alaska during January 1949 and as a result it wore insignia red Arctic conspicuity markings.The early flush-closing gun doors are fitted to this aircraft, giving a sleek look to the forward fuselage. Also visible are the 245-gallon ferry tanks (necessary for the long flight to Alaska), which are more bulky than the later combat tanks.The ferry tanks were in fact designed to be dropped in-flight but were superseded because their tapered aft section caused buffet. Author’s collection 14 aviationclassics.co.uk

This F-86A-5 was used by North American to test the ‘Mighty Mouse’ rockets that would become the weapon fit of the F-86D interceptor. 48-255 was based at China Lake Naval Air Station during February 1950 for these trials and a rack of four rockets can be seen beneath the left wing. It was later transferred to 1st Fighter Group and was written off in a landing accident on 17 November 1950. USN via Gary Verver of the P-86A-1 increased to 10,077lb though maximum takeoff weight remained the same.

However, with J47 power, the first P-86As could climb nearly 5,000 feet higher and the rate of climb was a much-improved 7,800 feet per minute. NAA listed the P-86A-1’s top speed at sea level as 585 mph – more than 70mph faster than the prototypes.

The P-86A-1 was the first ‘block’ of aircraft delivered, the ‘dash-1’ signifying this.

Subsequent P-86As (and later models of the aircraft) were therefore assigned numeric ‘block’ numbers to signify when significant changes had been made to the basic design.

Thus, in line with general USAF policy, the next variant of the P-86A would be the –5, and so on, raising in increments of five with each production change. In addition, if a significant modification was carried out after production, the vacant digits between each block number could be used, so that a modified P-86A-5 would become a P-86A-6.

The initial production block of 33 P-86A-1s were known by NAA as the NA-151, with serial numbers 47-605 to 637. The first aircraft from this batch took to the air from Muroc on 20 May 1948 powered by a J47GE1 engine and eight days later, this and the second production aircraft was delivered to the USAF. They were immediately bailed back to North American for test work.

Under the USAF aircraft designation changes of 1 June 1948, all P-86A ‘pursuit’ aircraft became F-86A ‘fighters’, though it was not until 16 July that the first F-86A was actually assigned to the Air Force. This machine, 47-608, went straight to the 3200th Proof Test Group at Eglin AFB in Florida. It then undertook most of the cold weather testing for the F-86A in Eglin’s climatic test facility, being subjected to temperatures as low as -65°F. 47-617 also took part in cold weather tests, this time at Ladd AFB in Alaska during January 1949.

Though many F-86A-1s were later assigned to operational squadrons, they were primarily service test aircraft and most were

This yellow-trimmed aircraft is from 27th Fighter Squadron, at the time part of the 1st Fighter Group at George AFB, California.These aircraft are seen at Nellis AFB during a gunnery deployment and the red-trimmed aircraft at rear is from 71st FIS. 1st FGp Sabres used a well-defined set of coloured tail bands: the upper band was painted in the squadron colour and the lower band was the Flight colour. Via Mike Fox assigned to various research programs. In particular, the third aircraft, 47-607, was retained at NAA for use as the static test airframe and was later transferred to Wright Patterson AFB in September 1948 for a similar purpose. Other testing duties comprised: performance and stability test (47-610 at Edwards AFB), armament test (47611), maintenance evaluation (47-614 and 615 at Chanute AFB), structural test (47-619), and engine control (47-621 with NAA). In addition, two F-86A-1s were handed over to the National Advisory Committee for Aeronautics (NACA): 47-609 was assigned to the Ames Laboratory for variable stability testing, and 47-620 to Langley, Virginia.

FRONT LINE ASSIGNMENT

The first active-duty squadron deliveries began on 14 February 1949. At that time, 47627 and 47-628 were assigned to 1st Maintenance Support Group of the 1st Fighter Group at March AFB, California.

They were then transferred to the first squadron to receive the F-86 – the 94th ‘Hat in Ring’ Fighter Squadron, replacing F-80

Shooting Stars. Between 15 February and 3 March a further eight 47-Fiscal Year F-86s were assigned and they remained with the 1st FG until July 1950 when newer F-86As arrived with the Group. All except one were passed on, mainly to Air National Guard units for familiarisation.

The remaining aircraft, 47-635, had been written off in a crash on 8th March 1950 while with the 94th FS, and thus started an unenviable trend. Despite these problems, from the outset the F-86 proved to be a real pilot’s plane. Jack Owen flew F-86A Sabres with the 81st FIW in England: “I flew F-86As for over a year which had been stationed at Bentwaters before being returned to the US. It was a delightful aircraft, uncomplicated; reminded you of a powerful sports car. On my third flight in the F-86, I had a fire warning light and vibrations. So I shut it down and glided about 80 miles from 30,000 feet and made a non-powered landing. It worked just as the book said it would. All the North American aircraft that I flew, I thought were outstanding; the AT-6 Harvard, B-25 Mitchell, P-51 Mustang and F-86 Sabre.” ➤ North American F-86 Sabre 15

The metal intake ring on this F-86A-5 shows that it has been upgraded to F-86A-7 specification with later gunsight radar. All F-86As came off the production line with a fibreglass intake ring and were modified with the later version after a few years in service.This aircraft is from 75th FIS at Suffolk County AFB during the second half of 1952. Lt Col A Goddard via Dave Menard

93rd FIS, based at Kirtland AFB in New Mexico was one of the lesser-known USAF F-86A units.The squadron flew they type July 1949 to August 1953.

Richard Escola

The first true production version of the F-86, the A-5, started to be delivered in March 1949, with completion of deliveries achieved in September of the same year.

The 188 aircraft in this batch differed primarily in being fitted with the J47-GE-7 engine. In addition, the forward windshield glass, which had been curved on the XP-86 and the F-86A-1, was changed to a vee-shaped item on the F-86A-5. A modified sliding canopy was also introduced which could be jettisoned in flight, and this canopy also featured a shorter Perspex section and correspondingly longer aluminium fairing at

In August 1950, 27th FIS was reassigned from 1st Fighter Group control and moved to Griffiss AFB on the east coast and attached to Eastern Air Defense Force.This magnificent photo of a hangar-full of 27th FIS Sabres dates from that time and shows 16 of the squadron’s 25-aircraft entitlement. Author’s collection 16 aviationclassics.co.uk

the rear so that an upper position light and the cabin pressure relief outlet could be mounted there.

The A-5 also introduced underwing pylons capable of carrying up to 1,000lb bombs or underwing ferry fuel tanks of 245 US gallon capacity. A heating system was provided for the gun compartments, and stainless steel fire-resistant oil tanks and feed lines were introduced. Beginning with the 100th F-86A, which was delivered in May 1949, an improved canopy defrosting system was installed, and a special coating was applied to the engine intake ring to reduce the effects of rain erosion.

This airframe also marked the introduction of an improved nosewheel steering system.

Earlier airframes were modified to incorporate many of these changes. All F86A-5s had provision for mounting the AN/ARN-14 radio receiver and AN/ARN-19 radio set.

Spin testing of F-86As had shown an unexpected problem with the slat system.

When the leading-edge slats opened or closed, instead of this being a gentle operation, aerodynamic forces often ‘slammed’ them in or out. To remedy this, from the fourth F-86A-5, a rubber snubber was installed along with a revised slat track radius. The 116th F-86A, 48-211, was the first to feature a new wing slat mechanism that eliminated the slat lock, and provided fully automatic operation.

Deliveries of 48-Fiscal Year (FY) F-86As to the squadrons began on 1 March 1949, and by early August 72 F-86A-5s had been assigned to the 1st Fighter Group. Starting in late March 1949, 17 F-86A-5s were also assigned to the 31st Fighter Escort Wing at Turner AFB in Georgia.

ANOTHER MYTH DISPELLED: FINAL DISPOSITION OF THE XF-86S The first prototype XP-86 was delivered to the Air Force on 3 December 1948 with just less than 98 flying hours to its credit and spent much of its short Air Force career as a test support aircraft at Edwards AFB. In May 1952 the aircraft was assigned to 4901st Support Wing at Kirtland AFB in New Mexico and from there it was transported (or possibly even flown) to Frenchman’s Flat at the Nevada Test Site (NTS) for use as a static test airframe in nuclear bomb testing. 597 survived at least two detonations – the ‘Encore’ blast of Operation Upshot-Knothole on 8 May 1953, and subsequently ‘Grable’ blast on 25 May.‘Encore’ was a 27 kiloton airdropped device and ‘Grable’ was a 15 kiloton fission weapon, delivered from a nuclear cannon.

It seems likely that if the historic first prototype survived these tests, it was then part of an 800 ton lot of aircraft scrap from the NTS which was offered for salvage in

For a short period confusion reigned, since the 31st had been slated to receive F-86s from the 1st Fighter Group, which would then revert to flying F-80s. However, it appears that few of these machines ever reached the 31st, and in any case the unit continued operating the straight-wing Thunderjet for a few more years and the 1st FG remained in the F-86 business. One aircraft, 48-181 appears to have been written off at Turner AFB on 26 May 1949 while assigned to the 31st FEW – it was reclaimed for scrap there by 1 June. All the remaining 31st FEW F-86As were reassigned to the 1st Fighter Group on 21 April 1949.

On 23 February 1949, a further 333 F-86A-5s were ordered under contract AC-21671 as NAA model NA-161. Serialled as 49-Fiscal Year (FY) aircraft, these machines were powered from the outset by the J47-GE-13 engine, now rated at 5,200lb of thrust. Other changes included simplified cockpit wiring, and from the 282nd F86A (49-1067), the wing was slightly redesigned, with a shorter-chord aileron and greater elevator boost. An AN/APX-6 radio replaced the SCR-695B from 49-1227 onwards.

The 49-Fiscal Year F-86A-5s began delivery in early October 1949, with the first few passing to the 81st FG. The 1st FG received its first 49-FY Sabre in January 1950 but the majority of the new aircraft did not begin to arrive with the wing until June of that year.

Ten of these aircraft were then lost in November 1950 to the 4th FG, which was just preparing to depart for the Korean theatre.

Other new Sabre wings also started to convert onto the type in 1950. The 33rd Fighter Interceptor Wing (FIW) at Otis AFB, Massachusetts, received its first six Sabres straight from Inglewood on 20 January and the 56th FG at Selfridge, Michigan also gained its first three brand-new F-86As in April of the same year. The final multi-squadron wing to receive the F-86A was the 23rd FIW, based at Presque Isle AFB in Maine. Its two squadrons

January 1965. Many authors have stated 597 was lost in a flying accident, but this is definitely not the case.

The second XP-86 was handed over to the USAF in May 1950 with something less than 96 flying hours and 180 flights to its name. It too served at Edwards AFB and was retired to the Aberdeen Proving Ground in Maryland during March 1953.

Total airframe time was just 202 hours and reports indicate that this machine may still exist on the Aberdeen ranges.

The third XP-86 aircraft was accepted by the USAF on 17 December 1948 with just nine hours flight time in 14 flights. It was assigned to Edwards AFB on various test programs, notably in armament testing.

Like the first prototype, it too was transferred to 4901st Support Wing at Kirtland where it was tested to destruction on 31 August 1952, presumably also at the Nevada Test Site.Total airframe time was just 75 flying hours.

received Sabres from 5 November 1951. In addition to the deployment of 4th FIW Sabres to Korea, one other Wing moved overseas with F-86As. During 1951, the 81st Fighter Group at Larson AFB in Washington state was alerted for a move to the United Kingdom and ferried its Sabres across the Atlantic in August 1951. Stationed at RAF Bentwaters and RAF Shepherds Grove the group replaced its F-86As with F-84F Thunderstreaks during early 1954 but would remain in England for more than 40 years.

THE AIR NATIONAL GUARD

From the summer of 1951, the F-86A began to be replaced in front-line units by the improved F-86E Sabre, and the ‘A’ models began to be released for service with Air National Guard (ANG) units.

The first ANG unit to receive F-86As was the 116th Fighter Interceptor Squadron (FIS), Washington ANG. This squadron had been called to active duty during the Korean War

This view provides a nice comparison of contemporary USAF and US Navy fighters: a 23rd Fighter Group F-86A-7 flies close formation with a Navy Grumman F9F-6 Cougar off America’s east coast. It is likely that the Navy fighter was on a test flight from Grumman’s Bethpage, New York factory.

Harold G Martin via Bruce Robertson prior to deployment to the UK with the 81st FG. Similarly activated units such as the 148th FIS Pennsylvania ANG received F-86As in February 1951, followed by the 142nd FIS Delaware ANG in May and the 123rd FIS Oregon ANG in October 1951. All these units were returned to State control within 18 months, and in the case of the 116th FIS many of its personnel and all of its Sabres were transferred to the newly activated 78th FIS. Other ANG units received single F-86As for training use in July 1950, but it was not until late 1953 that F-86As began to arrive for service in regular ANG squadrons.

The first of these squadrons was 190th FIS Idaho ANG at Gowen Field, which was assigned 48-240 on 30th September. By the end of 1953, five other National Guard squadrons had received at least half a dozen aircraft each, including the 116th FIS, Washington ANG, back in the Sabre fold after return to state control in November 1952 and a brief fling with the F-51D Mustang. ➤

This UK-based F-86A from 91st Fighter Interceptor Squadron (and parented by 81st FGp) appears to have made an off-airfield landing and is in the process of being recovered.The aircraft’s record card does record an unusual entry for ‘Wiesbaden’ (Germany) in December 1954 and this may be linked to the incident shown here. In any case, 49-1228 not only flew again but returned to the US in February 1955 and was last seen dismantled in a suburban back yard in Indiana in the 1980s. Dick Phillips North American F-86 Sabre 17

3525th Aircraft Gunnery Squadron at Nellis AFB in Nevada served as a fighter weapons school, training weapons instructors on the F-86A during the 1950s.This little-known unit operated F-86As in various yellow and black checkerboard markings and 491324 is seen here in typical ‘fighter bomber’ mode with two practice bombs mounted underwing. USAF As the Korean War raged on and surviving F-86As were rotated home in favour of latemodel Sabres, these aircraft were routed through overhaul at NAA’s Fresno plant and on to ANG squadrons. By the start of 1958, the majority of ANG F-86A units had either converted to more modern aircraft (often with later versions of the Sabre), or were in the course of disposing of their old Sabres. Most F-86As went to the massive storage and disposition facility at Davis Monthan AFB in Arizona, and the first of the type arrived there during October 1957. The last three ANG F-86A units were the 165th FIS Kentucky, the 192nd FIS Nevada and the 196th FIS California. They all sent their last ‘A’ models to Davis Monthan in early 1959. A few managed to escape the cutting torch, but for most the end was near; by December 1960 all F-86As at Davis Monthan had been authorised for reclamation and were soon scrapped.

THE P-86B

On 20 December 1946, Letter Contract W33-038ac-16013 (which also included 33 production P-86A-1s) was approved for 190 production P-86Bs. It is thought that the P-86B design was driven by the belief that enlarged

brakes (and hence larger wheels, which necessitated a wider fuselage) would be required because of heavy braking requirements on the aircraft once in service. In the event, advances in braking technology and specific training on braking technique with the early jets negated the need for the P-86B. Instead NAA proposed smaller, higherpressure tyres to the USAAF, and as a result the company was advised to cancel further work on the aircraft in September 1947 (NAA Airframe Contract Record dated 24 September 1947 records the event), and on 1 December NAA proposed instead that the P86Bs on order be cancelled in favour of 188 further P-86As (with 26-inch wheels) and two P-86Cs under the same contract.

After a short period of consideration, on 17 December the USAF revised this order as suggested, as Contract ac-21672. ■ Words: Duncan Curtis

Though designed for the photo reconnaissance role in Korea, a few RF-86As did return to the US and served with Air National Guard squadrons.They were valued for taking on cross-country trips because their vacant camera bays could house a great deal of personal equipment. 48-196 was assigned to 115th FIS, California ANG and based at Van Nuys.The re-contoured forward fuselage just in front of the wing root is the main clue to the aircraft’s previous career. Via Mike Fox

NAA’s Autonetics division was based at Downey in California and used this magnificent aircraft for unspecified tests from May 1950, basing the aircraft at Los Angeles International Airport. It is seen there at a display during 1956, when designated as a JF-86A test aircraft.

Sadly 49-1189 did not survive into recent times: it was retired to Davis Monthan in December 1957 and authorised for scrapping within six months of its arrival.

Emil Strasser via Dave Menard

18 aviationclassics.co.uk

Circa 1946, North American had proposed its second Sabre variant to the USAAF as the P-86B with NAA model number NA-152. It featured a number of changes to the basic XP-86/P-86A configuration as follows: 1. 30-inch diameter mainwheels (26-inches had been specified for the XP-86).

2. 7in wider fuselage (apparently dictated by the increased wheel/tire diameter in the retracted position).

3. Tail area increased by 6 sq ft.

4. Additional 60 gallons of internal fuel.

5. Gun and ammunition heating.

6. Ejection canopy.