Troubleshooting showed: Tire out of round and not balanced (probable cause of the fore and aft motion immediately after nose wheel touchdown); breakout force was 25 % low (probable cause of the wild divergent motion after about 1 second after nose wheel touchdown). Sequence seemed to be: (touchdown) (fore and aft motion) (skip to off center) (wild divergent lateral motion) (additional skipping) (trailed into normal position). SOLUTION: Reset breakout force 2 lbs over recommended by Van's; trued tire and had it balanced. NO RECURRENCE IN OVER 200 LANDINGS. Cockpit indications were rather mild, nothing that would indicate the seriousness of the problem. Glad we were testing Bill's new GoPro. Bob C.
Bob, I am breathless. WTF ! You said 'Wobble'. That was a near disaster (I think). If it happened ONCE then it can happen again. I have the Anti-Splat installed in the RV9A. But, I don't know if it would prevent a nose gear failure "should" it occur during this kind of wobble at these speeds. Great film for making us aware of things that can go wrong. VC at SE Ramp
Easy fix. Ask any Grumman pilot and you'll find out that the castle nut is too lose. Tighten so that it takes 10 to 15 pounds of pull to move the front wheel. Also, hold the nose off as long as possible.
Approach and land with full flaps at lowest possible airspeed. When main touched down, hold stick full aft, let speed decay and nose wheel come down and roll by itself gently. No brake application unless needed. Relax and do not anticipate any shimmy happening in your mind, relax.
If there is a problem like the one you have here you can be sure that the runway markings will help you find it , ask any motorcyclist about the centre line marking.
Accident at KCGI, one fatal, one injured. Probable nose wheel failure due to shimmy . Aircraft veered off runway and nosed over. DON'T FLY UNTILL the problem is resolved.
Fist thing I noticed was that when the flaps were out, there was no wobble. On the third landing, the flaps were taken out much quicker than the first also. Appears that the flaps may contribute to a little float making the wheel skip around. Just an observation.
Bill that nose gear problem will get worse if it’s not fixed. Please don’t fly this plane again until you have it repaired. Could be the castle nut on the thing of ma gig. It’s safe to say you should re-surface the entire runway and change your underwear. I been a TH-cam pilot for over 7 years.... Your Welcome!
Bob Hoover did say never fly the A model
Thanks for making this video my friend!
Troubleshooting showed: Tire out of round and not balanced (probable cause of the fore and aft motion immediately after nose wheel touchdown); breakout force was 25 % low (probable cause of the wild divergent motion after about 1 second after nose wheel touchdown). Sequence seemed to be: (touchdown) (fore and aft motion) (skip to off center) (wild divergent lateral motion) (additional skipping) (trailed into normal position). SOLUTION: Reset breakout force 2 lbs over recommended by Van's; trued tire and had it balanced. NO RECURRENCE IN OVER 200 LANDINGS. Cockpit indications were rather mild, nothing that would indicate the seriousness of the problem. Glad we were testing Bill's new GoPro. Bob C.
Heck Gee Gosh Dang. That is scary looking. That is why I built an RV-4 and RV-7. Tire roundness, break out and consider aftermarket anti squat brace.
Bob, I am breathless. WTF ! You said 'Wobble'. That was a near disaster (I think). If it happened ONCE then it can happen again. I have the Anti-Splat installed in the RV9A. But, I don't know if it would prevent a nose gear failure "should" it occur during this kind of wobble at these speeds. Great film for making us aware of things that can go wrong. VC at SE Ramp
Easy fix. Ask any Grumman pilot and you'll find out that the castle nut is too lose. Tighten so that it takes 10 to 15 pounds of pull to move the front wheel. Also, hold the nose off as long as possible.
Approach and land with full flaps at lowest possible airspeed. When main touched down, hold stick full aft, let speed decay and nose wheel come down and roll by itself gently. No brake application unless needed. Relax and do not anticipate any shimmy happening in your mind, relax.
If there is a problem like the one you have here you can be sure that the runway markings will help you find it , ask any motorcyclist about the centre line marking.
Accident at KCGI, one fatal, one injured. Probable nose wheel failure due to shimmy . Aircraft veered off runway and nosed over. DON'T FLY UNTILL the problem is resolved.
Fist thing I noticed was that when the flaps were out, there was no wobble. On the third landing, the flaps were taken out much quicker than the first also. Appears that the flaps may contribute to a little float making the wheel skip around. Just an observation.
Bill, what was the solution? I have the same thing happening on my RV-7A.
jessebell2355.....see the reply below from Bob Condon. This is his RV and his fix. It did seem to fix the problem two years running.
Thank...not sure how I missed that. I tightened the nut to a breakout force of ~28lbs...hoping that fixes it.
The solution is to convert it to a tailwheel!
probably nose gear wheel not Torqued enough.!
Bill that nose gear problem will get worse if it’s not fixed. Please don’t fly this plane again until you have it repaired. Could be the castle nut on the thing of ma gig. It’s safe to say you should re-surface the entire runway and change your underwear. I been a TH-cam pilot for over 7 years.... Your Welcome!
That was ugly, not sure how many of those the gear could handle. Makes me want a tail dragger.