Porsche Airqaft Engine

The following description of the Porsche aircraft engine has been received from the company and is reproduced here as being of interest to mony owners

The Porsche Company has now developed an aircraft engine and is proud to present it to the flying public alter having successfully passed the dynamometer tests of the Official German Aviation Research Centre in Brunswick'

We must stress particularly that the testing specifications and procedure of the German Aviation Research Centre are based on those of the'British Civil Airworthiness Requirements' which are among the most rigorous in the world and therefore assure the certification of the engine in all countries.

The Porsche engine completed these severe tests-which require among other things an endurance run of 150 hours-so that the test officials were able to fix the overhaul period at the comparatively high level of 600 hours'

This clears the way for the engine to go into quantity production which will not only fill a very vital gap in the European market but will allow the Porsche Company to present a new engine of sound design and many noteworthy features not offered by other engines in its class to the small plane designers and flying enthusiasts throughout the world.

General DescriPtion

The 65 h.p. (DIN) developed by the four-cylinder four-cycle horizontally opposed engine are transmitted via a special reduction gear to the propeller at 1,900 r.p.m. In this manner a high thrust .ffi"i.r"y can be obtained at a propeller diameter which is still practical for light aircraft'

The standard 160 watt/12 volt Bosch generator supplies sufficient current for all illumination requirements and instruments as well as the communications equiPment.

A special feature in this engine class is the electric starter fitted on the standard model which makes the pilot independent and avoids delay at take-off. A choice of two ignition systems is offered, both fully shielded, either dual magneto or dual battery ignition.

Dry sump lubrication assures satisfactory lubrication even during abnormal flight conditions. The oil consumption of 1.5 to 3.5 g/HPh (0.05-0.12 oz/HPh) lies in a very satisfactory range and the SJitre (5.3 U.S. quarts) tank provides an ample salety margin. The high speciflc output of 40 HP/l tr.(2.45 HP/cu. in.) is obtained by the use of a dual down-draft carburettor of high angular stability for use in planes with normal and utility classification, permitting simple stunt patterns such as loops, rolls and steep turns to be flown.

The top speeds obtainable with this new Porsche engine will depend on aircraft type but ranges up to about 200 km/h (135 m.p.h.). Fuel consumption is low, between 2l litres/h (5'6 gaIs.h) at 65 take-off HP and 15.5 litres/h (4.1 gals.h) at 50 HP cruising.

The standard equipment includes wet air-filter, anti-icing and pre-heat system as well as cockpit warm-air supply. Looking forward to stricter noise level regulations the Porsche Company has also equipped this aircraft engine with a highefficiency exhaust muffiing system found on few other engines of this size.

The price for this engine will include all these items as standard equipment of the production rnodel.

In a second version the basic engine is used as described above but fitted with two dual carburettors as well as a cooling blower. This engine has been designed to be installed within

Technical Data

PORS(HE Aircraft Engine Type 67811

TAKE.OFF OPERATION LIMIT:

FUEL:

OIL:

.OIL CONSUMPTION:

DRY WEIGHT:

TorAL wErcHT, including cowling, starter, generator, heating unit, muffier, ignition shielding:

PROPELLER ROTATION:

AIR WORTHINESS RATING:

INTERFERENCE SUPPRESSION:

TEST PROCEDURE: the fuselage of the aircraft and employs a reduction ration of I .74 : I combined with a somewhat higher power output. The installation dimensions were kept to a minimum in order to provide favourable conditions for pusher screw designs. The take-off power is delivered at 2,600 propeller r.p.m.

Besides these two engines a lighter and simplified power plant, of the same basic type, delivering 50 HP at 3,300 r.p.m. but weighing only 154 1b., also with dual ignition and carburettor pre-heat system although without electric starter, has been developed for very small aircraft. Take-off

5 minutes

80 octane aviation fuel

Shell Rotella SAE 30

1.5-3.5 g/HP/h (0.05-0.12 ozlHP/h)

87 ke (1921b.)

105 kg (2321b.) in flight direction clockwise restricted, categories N and U only; not suitable for snap or inverted mancuvres fully shielded according to British Airworthiness Requirements by Official German Avia- tion Research Centre, Brunswick

Design Characteristics

TYPE:

CYLINDER ARRANGEMENT:

BORE:

STROKE:

PISTON DISPLACEMENT:

COMPRESSION RATIO:

IGNITION:

FIRING ORDER:

FUEL SUPPLY:

CARBURETTOR: AIR FILTER: ELECTRICAL SYSTEM:

MISCELLANEOUS:

4 cylinder, 4-cycle gasoline engme in pairs, horizontally opposed (boxer)

2 spark plugs for each cylinder with dual coil or dual magneto l-4-3-2

I Diaphragm-pump Dual downdraft carburettor wet filter

Bosch generator 160 watt/ 12 volt shielded with voltage regulator Exhaust muffIer; heating system for cabin; carburettor pre-heat system