NTSB Factual Report

On July 4, 2017, about 0905 mountain standard time, a Vickers Supermarine Ltd Spitfire V airplane, N5TF, was substantially damaged during landing at Marana Regional Airport (AVQ), Marana, Arizona. The airline transport pilot was not injured. The airplane was registered to Comanche Fighters LLC and operated by the pilot under the provisions of Title 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed at the time of the accident. The personal cross-country flight originated from the Las Cruces International Airport (LRU), Las Cruces, New Mexico, about 0850.

In a statement submitted to the National Transportation Safety Board investigator-in-charge, the pilot reported that after making a normal landing on runway 12, and as the airplane slowed on rollout, it started to drift to the left. When rudder input was ineffective [to counter the left drift] due to the slow speed, right brake was applied. The pilot stated that the brake grabbed enough to start the airplane's nose to swing to the right. At this point left rudder and brake were applied to counter the right swing, however, rudder input was again ineffective and left brake provided no stopping action. The pilot opined that without left brake there was nothing to stop the right swing due to the free swiveling tailwheel. The airplane subsequently departed the right runway edge, impacted soft dirt, which resulted in the collapse of the left main landing gear. The airplane came to rest upright and on its nose. The left wing was substantially damaged as a result of contact with terrain. The pilot mentioned that upon activation of the left brake the pressure felt normal but no braking action was received. The pilot added that the brake acted like it was hot, even though this was the first activation during the landing.

On August 8, 2017, under the supervision of a Federal Aviation Administration airworthiness inspector, a postaccident examination of the brake system by maintenance personnel familiar with the vintage airplane was performed in a secured facility at AVQ.

The inspector reported that the airplane's brake system is an air system that works from an engine driven compressor, which maintains system pressure at 300 psi. There is also a ground service filler for nitrogen that is to be added before flight if the system loses pressure while the engine is not running. The inspector further reported that the yoke has a squeeze handle to operate both brakes. If the left rudder pedal is moved, the system will move the brake pressure to the left wheel. If you move the right rudder pedal the system will move brake pressure to the right wheel. This happens through the brake relay valve. There is also a preset pressure of between 80 and 120 psi to each wheel.

The inspector reported that when the examination began the system was at zero psi, and that it was normal for the system to bleed down to zero when not being operated, especially if the flaps are in the down position (flaps were in the down position at this time). When the brake system was serviced to approximately 170 psi to test the system, it tested normally. The pressure to each wheel was normal at 110 psi. The inspector stated that during the examination the brake system appeared to be working as designed. Additionally, the inspector reported that the tail wheel system was tested and appeared to also function normally.

The inspector mentioned that in speaking with pilots who flew the Spitfire, the airplane is very difficult to land on a runway, and that it was made to land in a field or grass [airstrip]. Additionally, he was told that when the brakes get hot the brake system can get very spongy. The inspector also mentioned that the pilot said he had lost the left brake. A survey of the runway revealed a 200-ft skid mark from the left main tire. There was no observable damage to the tire that was consistent with the left brake having locked up. Wind at the time of the accident was reported to be 230° at 3 knots.

NTSB Probable Cause

The pilot’s failure to maintain directional control of the airplane during the landing roll.