rv7boy
Forum Peruser
An introductory note of explanation: Several months ago, there appeared in these forums a thread that was posted in the "Temporary" forum relating to a recent RV accident involving possible brake problems. Bob Axsom posted some excellent thoughts and as one of the moderators, I captured his post and saved it to my hard drive. I contacted Bob and asked his permission to edit it slightly to remove references to the accident with the thought of re-posting it here in the "Lessons Learned" Forum. For whatever reason, Bob and I never had further contact about publishing his post. I didn't have his email address, which apparently was hard to get, and he was rather busy. So his edited post sat on my hard drive for several months.
We just received word yesterday of Bob's passing, and with respect to him, I am sharing the last version of his post relating to his brake experiences on his RV-6A. Even though it's been edited slightly, his frankness and his willingness to help other RV-A pilots are easily noticed. I share this with the VAF community because I think Bob would be okay with me doing so. Thanks, Bob.
Sincerely,
Don Hull
One of the moderators
My RV-6A Brake Experience
April, 2013
By Bob Axsom
With Van?s nose gear series (A series) RV airplanes, there is no nose gear steering. The typical reason for the "A"s to go off the runway is brake failure.
The failure of brakes is not an ?always the same? linear experience. I've had it happen three times:
1 - once because the O-ring in the master cylinder was cut in manufacturing assembly in the Cleveland manufacturing process (found when the brake fluid leaked onto the cockpit floor long before flight). Installed factory overhaul kit to repair - new O-ring.
2 - once when the I let the brakes wear down too much (always the right brake of course) and the fluid ran out on the ramp at Panama City Beach, FL (Thought I could handle it and started the engine, spun around the left main tire which still had a brake - didn't hit anything - added ?replace brakes? every year to my annual condition inspection checklist); Borrowed a new O-ring for the slave cylinder piston from a local RV builder and flew home.
3 - Once when I got on the brakes to make the first turn off at Prescott, AZ (a little show that went wrong) the flare on the brake line failed on the right brake (probably related to all the disassembly/reassembly operations in Florida). The failure occurred part way into the turn-off and the pedal went flat and the taxi straightened right toward a taxiway light. I knew I still had left brake from my Florida experience and I used it to avoid the light. Got towed to the ramp with a dolly under the right wheel. Rented a flare tool from a maintenance shop on the field repaired the line, replace fluid and continued trip.
Two other excursions off the runway occurred because of tire failure - one left and one right - those cheap tires are so thin they can fail on a single incident of aggressive braking (sorry I sometimes don't always pussy foot around like I want my instructor to smile proud). After the second failure I bought three tires from aircraft Spruce and compared the different models side by side, by weight and inspection and reported the findings here in the VAF forums. I went with the Goodyear Flight Custom III tires and Michelin Airstop tubes from that point on.
I have been flying the RV-6A that Jeanine and I built in our garage since I made the first flight in March of 2004 with no more landing gear/brake related problems. If this information helps someone that will be great.
Oh one more thing - I never ever fly without the landing gear fairing on the nose gear and I developed subfairings for drag reduction on all three wheels for my personal use that have scraped more than once. You would be surprised how strong the fiberglass is, even against raw concrete, and it will prevent the unopposed strut grab of the naked gear.
Bob Axsom
.
.
.
We just received word yesterday of Bob's passing, and with respect to him, I am sharing the last version of his post relating to his brake experiences on his RV-6A. Even though it's been edited slightly, his frankness and his willingness to help other RV-A pilots are easily noticed. I share this with the VAF community because I think Bob would be okay with me doing so. Thanks, Bob.
Sincerely,
Don Hull
One of the moderators
My RV-6A Brake Experience
April, 2013
By Bob Axsom
With Van?s nose gear series (A series) RV airplanes, there is no nose gear steering. The typical reason for the "A"s to go off the runway is brake failure.
The failure of brakes is not an ?always the same? linear experience. I've had it happen three times:
1 - once because the O-ring in the master cylinder was cut in manufacturing assembly in the Cleveland manufacturing process (found when the brake fluid leaked onto the cockpit floor long before flight). Installed factory overhaul kit to repair - new O-ring.
2 - once when the I let the brakes wear down too much (always the right brake of course) and the fluid ran out on the ramp at Panama City Beach, FL (Thought I could handle it and started the engine, spun around the left main tire which still had a brake - didn't hit anything - added ?replace brakes? every year to my annual condition inspection checklist); Borrowed a new O-ring for the slave cylinder piston from a local RV builder and flew home.
3 - Once when I got on the brakes to make the first turn off at Prescott, AZ (a little show that went wrong) the flare on the brake line failed on the right brake (probably related to all the disassembly/reassembly operations in Florida). The failure occurred part way into the turn-off and the pedal went flat and the taxi straightened right toward a taxiway light. I knew I still had left brake from my Florida experience and I used it to avoid the light. Got towed to the ramp with a dolly under the right wheel. Rented a flare tool from a maintenance shop on the field repaired the line, replace fluid and continued trip.
Two other excursions off the runway occurred because of tire failure - one left and one right - those cheap tires are so thin they can fail on a single incident of aggressive braking (sorry I sometimes don't always pussy foot around like I want my instructor to smile proud). After the second failure I bought three tires from aircraft Spruce and compared the different models side by side, by weight and inspection and reported the findings here in the VAF forums. I went with the Goodyear Flight Custom III tires and Michelin Airstop tubes from that point on.
I have been flying the RV-6A that Jeanine and I built in our garage since I made the first flight in March of 2004 with no more landing gear/brake related problems. If this information helps someone that will be great.
Oh one more thing - I never ever fly without the landing gear fairing on the nose gear and I developed subfairings for drag reduction on all three wheels for my personal use that have scraped more than once. You would be surprised how strong the fiberglass is, even against raw concrete, and it will prevent the unopposed strut grab of the naked gear.
Bob Axsom
.
.
.
