Safety Accident Reports
Strip hazards
Steve Ayres summarises and comments on accident reports from around the world and looks at some rather nifty tyre pressure sensors which might just warn of an impending flat…
Bogged down Bristell NG5 Speedwing G-COLF Tiger Moth G-BAFG Private Strip, Birdsedge, Yorkshire Injuries: None
While backtracking, the pilot of G-COLF noticed an area of undulating soft ground across Runway 08. After turning around at the threshold, he taxied forwards to position beyond the area before starting his take-off. While crossing the ground the aircraft became bogged down and the pilot applied increasingly more power to overcome the resistance. G-COLF’s power setting increased to such a level that bystanders thought it was starting its take-off run. They then saw the nosewheel caster left before the aircraft veered off the runway and collided with G-BAFG on the adjacent grass parking area. The pilot of G-COLF believed his aircraft may have become stuck in a rut on the runway, leading to the left wheel spat digging into the ground and causing the aircraft to pivot under power. The proximity of G-BAFG to the runway edge meant that the accident pilot had little time to react before the collision. By their nature, unlicensed airfields can have their own specific hazards, to which pilots need to be alert. In this case, parked aircraft near the runway and high power, to avoid bogging down in undulating soft ground were catalysts for an accident. Comment We’ve all been there – forgotten to remove the chocks, park brake left on or bogged down. In this instance it had to be the latter,
especially as the bad ground had been spotted on the way out to the threshold. But there’s only so much power that’s safe to add before stopping to think through the potential consequences of adding more… something will ultimately give way!
Misalignment – 1 Piper PA-38-112 G-BPPF Compton Abbas Airfield Injuries: None
The pilot was visiting Compton Abbas Airfield and, having taxied out for departure, proceeded to line up on what he thought was the runway. However, he had actually lined up to the left of the runway. During the take-off roll, the aircraft pulled to the left, which was subsequently diagnosed as a binding left brake. This, combined with his starting position, meant he got close to a line of parked aircraft. The pilot described that he lined up to the right of what looked like two ‘black cones’. The UK Aeronautical Publication (AIP)1 page on Compton Abbas details the runway markings which include black and white runway threshold markers positioned to the side of the runway threshold. The pilot of G-BPPF probably lined up between the marker board and the left side chalk line of the runway. It’s the AIP that contains validated aviation data, but image tools such as Google Earth can be useful to pilots who are visiting places with which they may not be familiar. While they do not give detailed, up-to-date info, they can add a visual image of what to expect.
“Unlicensed airfields can have their own specific hazards, to which pilots need to be alert” 46 | FLYER | February 2021
Misalignment – 2 Replica WAR FW190 G-CCFW Lower Upham Farm Airstrip, Marlborough, Wiltshire Injuries: One serious
The pilot was flying G-CCFW, a Replica WAR FW190. The skies were clear with bright sunshine and light winds from the south-west. At around 1200, the pilot returned to the airstrip to land on its southerly runway. On landing, the aircraft had travelled a short distance when it ‘stopped violently’ and pitched over onto its back, trapping the pilot. The pilot was removed from the aircraft by emergency services and had suffered serious injuries. The aircraft was damaged extensively and deemed uneconomic to repair. The aircraft had landed in crop to the left of the grass runway. He reported that he mistook the unmarked grass runway to be part of the crop in the adjacent field to the right of the runway owing to its similarity in colour. Instead, he made an approach to and landed in the field to the left of the runway, where tractor marks and the edge of the grass airstrip had created the appearance of a ‘false’ runway similar in size and shape. The sun overhead may have reduced the contrast between the grass strip and the crops, contributing to the reduced conspicuity of the grass airstrip. The pilot reported that the runway has since been marked out with white chalk lines. Comment It’s that time of year again. Any markings on grass quickly get washed away or muddied, sun angles can be blindingly low, colour contrast between landing surfaces and their surrounds, poor. Having only recently averted an off-strip touchdown myself by catching sight of much rougher terrain than expected beneath me, I know how easily it can happen. All it cost me was an additional landing fee although, as these events highlight, the outcome is sometimes extremely serious. And such occurrences are sadly not restricted to
