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Nose wheel Tipover Incident Prevention System (TIPS)

Ron Lee

Ron Lee

Well Known Member
After seeing the 7A flipover in England I had my 6A nosegear shortened 1 inch by Langair. This required the shorter nose wheel fork.

This past week I added carbon fiber to the front part of the nose wheel pant to act as a skid plate in case I encounter a rut/pothole.

I have three layers going from the bottom up to the tip. Two on each side towards the back then two across the tip (left to right).

It is strong and was designed according to sound TLAR engineering practices.

NosePantCarbonFiber.jpg
 
Just curious...

What makes a 1" shorter nose gear less succeptible to fold over?

My recollection is that most of 'em that fail suffer a failure down near the nose wheel, rather than up at the mount.

FYI, I was at the Thomasville fly-in today and noticed that probably 6 out of 7 of the -A models I saw land had a fore/aft nosewheel shimmy. I've noticed it before and have always suspected that if you hit a bump at the wrong point of the fore/aft shimmy, it might be a bad thing.

Any idea on what causes that shimmy? Bearings that are not allowing the wheel to rotate freely? An out of round or balance tire?
 
Don't know about fore/aft motion

My "cure" is to prevent the nut at the bottom of the gear leg from digging into dirt and acting as a pole vault.
 
Mike S said:
George????

Is this a new short post record???
Click to expand...

:p

I love it!

George, this is a direct violation of the 1,000 word minimum ruling you have been self-imposing here on VAF for as long as I can recall.

Please go back and rephrase your last post in a way that requires more elaborate wording and greater clarification.

Why use one sentence when a paragraph will do?

Please hook a brutha up!

;) CJ
 
Ron Lee said:
After seeing the 7A flipover in England I had my 6A nosegear shortened 1 inch by Langair. This required the shorter nose wheel fork.

This past week I added carbon fiber to the front part of the nose wheel pant to act as a skid plate in case I encounter a rut/pothole.

I have three layers going from the bottom up to the tip. Two on each side towards the back then two across the tip (left to right).

It is strong and was designed according to sound TLAR engineering practices.

NosePantCarbonFiber.jpg
Click to expand...

You need to consider where the load is being transferred. Just strengthening the nose cone won't do it-- the load will just transfer to the screws attaching it to the aft wheel pant. These screws will fail or tear out.

My solution was to ensure that the load transfers to the front/bottom of the fork, pitching it up to correct any tucking under tendency. It's also been (ahem) tested.

Search the threads for more detail.
Vern
 
Kyle Boatright said:
Just curious...

What makes a 1" shorter nose gear less susceptible to fold over?
Click to expand...

That's the 1" reduction at the end of the leg and re-threading in order to fit the new style Vans nosewheel yoke. The wheel stays in the same place, but the nut moves up 1" to give it more ground clearance.
 
Ron definitely is on the right track raising the nut and adding strength to the fairing. It does act as a ski, sometimes, and has a much larger foot print than the tire. But it sure is not bullet proof.

It was 4 years ago (10-13-03) when I did the pogo ride in a bean field. The strut and wheel assembly did not break even with the entire weight of the airplane on it as it went over, it just bent back about 4 inches. For those interested, this is the final report on the event.

http://www.ntsb.gov/ntsb/brief.asp?ev_id=20031017X01762&key=1

I fly out of a grass strip and so far all has gone well since, probably a 100 hundred or more landing at this airport, but I never stop thinking about the possibility of it happening again. The nose fairing HAS acted as a ski more than once with a wet surface as the tire sunk in the soft turf. I don't like it but no one around here is interested in spending a $100 plus grand to pave the patch as most of the guys are more interested in keeping things as they are - warts and all. Nice green grass is appealing although this year it has been burned brown dry with the continuing draught and extreme temperatures.

The "A" models are, IMHO, 99.9% safe with regard to the nose wheel. But the potential for being bitten is always there if the NG comes down hard, even on a hard surface. Being in the habit of controlling final speed and shooting for a full stall landing, whenever possible, is my technique and so far it is working. When the nose does come down, it is as gentle as possible.

 
Last edited:
No guarantee that this will work...possibly better than nothing

While some other part may fail in the event of hitting a pothole/rut, the intent is to have the skid plate last long enough to prevent the bottom of the nose gear leg/nut from catching and acting as a pole vault. It only has to last a tenth of a second or so to do this.

Remember that this is TLAR (That looks about right) analysis.
 
Ron Lee said:
After seeing the 7A flipover in England I had my 6A nosegear shortened 1 inch by Langair. This required the shorter nose wheel fork.

This past week I added carbon fiber to the front part of the nose wheel pant to act as a skid plate in case I encounter a rut/pothole.

I have three layers going from the bottom up to the tip. Two on each side towards the back then two across the tip (left to right).

It is strong and was designed according to sound TLAR engineering practices.

NosePantCarbonFiber.jpg
Click to expand...

Full back stick when braking often works!!
 
This is definately one of the issues that makes me question myself on rather to get a 7 or 7A... I dont do much landings or takeoffs on grass strips... but once I build a plane, I'd like to have the ability to do such should I choose...
 
I second the thought on being concerned about the nose wheel. I've talked to Van's numerous times and they always point toward pilot technique... hard to believe after looking at some of the write-ups and experience involved(?). I own a grass strip & plan to build a house out there next year... and just ordered my QB fuselage as a 7A (the concern is offset by keeping the building partner wife happy). However the engineer in me is hard at thought... anyone aware of other mods/redesign to improve the nosewheel pole vaulting threat on rough fields? My fuselage isn't due until JAN so time to think and look around before getting radical (or changing my mind & dropping the "A" ...). I know this is a loaded question but any ideas? Doug
 
N770TX said:
I second the thought on being concerned about the nose wheel. I've talked to Van's numerous times and they always point toward pilot technique... hard to believe after looking at some of the write-ups and experience involved(?). I own a grass strip & plan to build a house out there next year... and just ordered my QB fuselage as a 7A (the concern is offset by keeping the building partner wife happy). However the engineer in me is hard at thought... anyone aware of other mods/redesign to improve the nosewheel pole vaulting threat on rough fields? My fuselage isn't due until JAN so time to think and look around before getting radical (or changing my mind & dropping the "A" ...). I know this is a loaded question but any ideas? Doug
Click to expand...

Doug,
I understand your concerns, thoughts of the nose geat folding used to keep me awake at night. I have only flown my 9A about 45 hours in total so I can't speak with great authority, however, the more I fly, the more impressed I become with the design and strength of the nose gear assembly. I have done many practice short field landings (some less than perfect) with hard braking on different grass strips and now have the aircraft operating from my grass farm airstrip. I modified the nose cone fairing and IMHO this has increased the safety margin considerably.
See my post for more details:
http://www.vansairforce.com/community/showthread.php?p=144823#post144823

Fin 9A
 
Dare to be different...

N770TX said:
I second the thought on being concerned about the nose wheel. I've talked to Van's numerous times and they always point toward pilot technique... hard to believe after looking at some of the write-ups and experience involved(?). I own a grass strip & plan to build a house out there next year... and just ordered my QB fuselage as a 7A (the concern is offset by keeping the building partner wife happy). However the engineer in me is hard at thought... anyone aware of other mods/redesign to improve the nosewheel pole vaulting threat on rough fields? My fuselage isn't due until JAN so time to think and look around before getting radical (or changing my mind & dropping the "A" ...). I know this is a loaded question but any ideas? Doug
Click to expand...

...and land on the mains first!

"high time" pilots flip aircraft, stall on approach, make controlled flight into terrain, and continue VFR flight into worsening IMC. Watch the landings at an RV fly-in and you will quickly understand why there are so many flip-overs. Also, check out the elevators during taxiing---sadly, most won't be in the appropriate position.

Lots of "A's" out there landing just fine on unimproved surfaces(but avoid the really rough stuff).
 
Thanks guys, I like the fairing mods and looks like some good ideas. Are you flying yet and any performance +/- or trim difference that you can tell? I'll probably bug you for even more detail as I get closer to that point. As for the other comments, I think my grass is one of the best I've ever seen and with a nice crown. Although we all get used to things after a while... I've had a few passengers in my C150 or C172 that have never been on anything but pavement comment that the turf is kind of rough - amazed me(?)! I did have another friend recently land his turbo C310 out there and other than looking HUGE he had no problems. You're all welcome to drop in if ever out our way (TS35). I have a bit of experience and always consider landings a specialty and one of the most satisfying things you can do every flight and I've seen some rough RV landings that amaze you with no issues but I've also seen a couple of those videos where it wasn't logical that the airplane is suddenly going on its back. I can see my sons flying my RV someday without my thirty five + years experience and ... of course I do occasionally do a dumb thing in an airplane myself. I hope to continue learning but the difference between a learning experience and a statistic is pretty hard to define... Bottom line is I'm comfortable enough with the design that I'm going the 7A route for all of its other advantages but that doesn't mean it can't be tweaked here or there... The nagging part is that I know this isn't an issue with the conventional gear and I sure don't want to be sitting there someday hanging from the straps looking over at my Starduster 2 and saying "I should of put a tailwheel on it...". Finley I think you're on the right track! (now the NASA part of me is thinking if I incorporate a little titanium into that......)

Thanks guys, fun post! Best regards - Doug
 
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