What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

RV tipple over update from UK

Stick was fully back

The stick was back, judging from the elevators, as it should be. I wonder why the nose wheel fairing was off?
 
"A" drivers look out

Just what we needed, more fodder for the tail-wheel guys. Since all the debate on this forum about the possibility of "A" models flipping on grass it has become one of my biggest concerns in building since I like to love frequent grass strips. I'm sure glad they were alright in this case. Just what scares me, nice day at a fly-in, nice weather with your "already scared to death of flying" wife strapped in next to you and everything goes terribly bad in a few seconds. Does anyone know how to get a copy of an accident report like this from the UK. That missing nose fairing is very interesting.
 
There have been so many of these happen even at walking pace that I just never land on grass and don't even taxi on grass. I will hand pull or push my 6A on grass with my tow bar because I can see and steer clear of dips and animal holes.

All it takes is something less than 2 inches deep and fairly abrupt and this is what will happen at any speed over 5-10 knots.

What a shame. Glad everyone was ok. I'll be sure to keep packing my canopy breaker hammer onboard. Scary thought if this happened where nobody was around to help or the airplane caught fire.
 
hevansrv7a said:
The stick was back, judging from the elevators, as it should be. I wonder why the nose wheel fairing was off?
Click to expand...

When is VANS going to wake up and acknowledge that there is a problem with the strength, (or lack of) with the A model aircraft nose wheel gear leg!!! There has been way to many of these nose over events occur.
 
RV tip over (flip upside down)

Does anyone know whether this was at touch-down or roll-out? If this happened at touch-down, full up elevator should hold the nose wheel off. If not, the landing speed was much too slow. That would explain a lot. If it happened during during roll-out, then that's a different story.
I agree with others that the missing fairing is interesting. Was there a previous problem with the nose wheel?
 
Last edited by a moderator:
In the end, a wheel diameter change might reduce the frequency of these accidents. The lamb wheel RV's use has a fairly small diameter and simply doesn't have the same ability to cross irregularities as larger wheels.

Of course, to do that, you'd need a diffrent nose wheel fork, a different wheel and tire, a different nosewheel fairing, and might need to add vertical stabilizer area to offset the added area up front...

On the other hand, the wheel diameter issue really doesn't explain the odd fore and aft shimmey that many -A's have, even on smooth paved surfaces. I've always thought it might be a contributing factor to nose wheel failures - the scenario would be the nosewheel hitting a minor bump at the "wrong" point in the fore/aft oscillation cycle..
 
My guess about the fairing is that he removed it before flying to this event to decrease his chances of a nose over. It is possible he removed it to repair something and was keeping an eye on a possible poor repair. Anybody have any other ideas?
 
On the runway

Mel said:
Does anyone know whether this was at touch-down or roll-out? If this happened at touch-down, full up elevator should hold the nose wheel off. If not, the landing speed was much too slow. That would explain a lot. If it happened during during roll-out, then that's a different story.
I agree with others that the missing fairing is interesting. Was there a previous problem with the nose wheel?
Click to expand...
Mel... I was going to say it was a taxiway, but the runway at the airport is only 40 ft wide. There seem to be no defined taxiways...

http://www.defford-croftfarm.co.uk/airfield.htm

Your question still stands.... perhaps a UK RVer can answer?

gil in Tucson
 
Old yoke

Looks like it had the old style wheel yoke.
***Correction*** I mean fork.
 
Last edited:
My guess it that the nose wheel fairing was removed to prevent damage to it or already had the crackies due to previous terracontactus and was being repaired back at the shop.

Be careful. One busy digging gopher or a damp strip can ruin your day.
 
The last pic in the sequence sickens me, the fuse is badly crinkled just aft of the canopy as best I can tell!!! :(

Major repair ahead if even possible due to cost vs value. Am I wrong?? Whole new fuse?? Probably tweaked the firewall too, engine tear down, prop???

Poor *******.
 
Yukon said:
Or.............when will A models quit landing on grass strips?
Click to expand...


It appears that Roberta Hegy (RV7A) & Jerry Thorne (RV9A) fly grass strips on a regular bases.

Perhaps they're just better pilots than some tail wheel dudes... :D

L.Adamson
 
Pilot skills play a minor if any role here. Fact, if the fork noses into terrain abruptly and hard enough, the leg will fold. I know many people have got hundreds of grass strip landings in A models without incident. If the strip is smooth, dry and had no recent rodent activity, you won't have a problem but if one of these things is not the case...well, undoubtedly more cases will be added to the stats in the coming years. :(
 
Yep, looks like the old -A fork, but you said it on **** from tailwheel builders/flyers. If grass is your mission, either build/buy a Tailwheel RV or tighten your seatbelts and over-insure, because you never know what will flip you over. Most likely you won't even see it coming at all.
 
osxuser said:
Yep, looks like the old -A fork, but you said it on **** from tailwheel builders/flyers. If grass is your mission, either build/buy a Tailwheel RV or tighten your seatbelts and over-insure, because you never know what will flip you over. Most likely you won't even see it coming at all.
Click to expand...

There is certainly some tail wheel bias on this forum. But if grass & going a bit farther, un-paved strips are really your mission, then get an Aviat Husky, Maule, Cessna 180, or something similar. But stay out of those down drafts! :)

What are still small diameter front wheels on an RV taildragger, are not the best application for unseen rodent holes, etc. Let's face it, even the RV taildragger is not a tailer made "bush" machine. Any RV in the rough, is still somewhat of a gamble.

L.Adamson
 
In regards to Mel's question about landing speed....certainly a possibility of coming in too slow. The first picture could be mid-rebound after pancaking in. With that much up elevator, one would think the nosegear would be off the ground otherwise.

One thing that I notice is there seems to be a little bit of a "dip" in the runway in the first picture. You can tell that the airplane did not travel far after the first picture was taken by where the airplanes are in the background in the second shot when it started going over. Perhaps rollout speed was just fast enoungh that the nose gear flexed aft as it came up the dip. Then the old version nosegear fork dug into the dip's incline and the rest was history.


Until I get REAL comfortable with my landings and I am REAL familiar with the strip, N782P will not be seen landing at any grass strip.
 
I agree that it *seems* like the A models are more prone to the flip over problem. Jack Holland and I went to a flyin yesterday in his 7, and on the taxi in, we went over a hole that REALLY got our (especially his) attention. That hole would've been a REAL problem with a nosewheel airplane. TD's flip too, but jeez, be careful Aer's! :eek:
 
The old version nosegear?

painless said:
Then the old version nosegear fork dug into the dip's incline and the rest was history.
Click to expand...
Now you opened up a can of worms for me. :confused: What exactly is the old version nosegear and when did Van's change it?
Also do you think its a issue of a little nose wheel falling into a hole or the extra shock actually collapsing the gear leg? :eek:
 
NYTOM said:
Now you opened up a can of worms for me. :confused: What exactly is the old version nosegear and when did Van's change it?
Also do you think its a issue of a little nose wheel falling into a hole or the extra shock actually collapsing the gear leg? :eek:
Click to expand...

Around 1999, Van's produced a new & more robust nosegear leg for the RV6A's. A replacement was about $135.00.

The nose gear that I believe they're referring too, is where the front end of the nose fork is raised, compared to being level on the older models.

L.Adamson
 
robertahegy said:
Looks like the mains and nose gear are severely splayed out from a very hard landing (first pic), possibly a full stall landing. The correct deflection of the elevator would have kept the nose gear up and out of harms way if the approach and speed were correct. This elevator looks like the pilot may have over-reacted to an impending stall during the flair. Way too high for a normal flair. From what I see, the runway looks marvelous. Glad the people are OK.

JMHO

Roberta
I fly from a 1700 ft grass strip. WI69
Click to expand...

Roberta,

I just don't see anything wrong with his mains, hard as I try! Assuming he is landing into the wind, his landing rollout should be made with full up elevator
to prevent the nosewheel from digging into a hole :( Just can't draw any conclusions other than he hit a gopher hole or rough spot.
 
Old vs New Fork

STUFF%20034.jpg
 
If you pancake or wheelbarrow an A model on even a paved runway you are asking for trouble and on grass- cross your fingers with full aft stick. Touch on the mains with nose high. Half flaps will give you a lot more elevator authority in the flare if your C of G is near the forward limit than full flaps.
 
You could be right, John. An abberation in the surface may just have been the cause. I never use full up in a landing flair, though, and the speed at a proper touchdown, full up would have you setting up for the second touchdown. And that might not be pretty.

I do agree that you should never do anything in an airplane that you are not comfortable with, competent, and qualified in doing. Only the pilot will know what really happened. I apologize for any speculation. The PIC will always, and should always, be held accountable.

Roberta

Terminal Van's Cheerleader!!! :p
 
Last edited:
rv6ejguy said:
If you pancake or wheelbarrow an A model on even a paved runway you are asking for trouble and on grass- cross your fingers with full aft stick. Touch on the mains with nose high. Half flaps will give you a lot more elevator authority in the flare if your C of G is near the forward limit than full flaps.
Click to expand...
There is a -9A in this area that pancaked in on a paved runway and got VERY lucky. He had to replace the nose gear, fork, prop, and got an engine OH out of it. When it was said and done, the fork was bent such that the gear leg bent backwards and the fork was pointing straight up in the air.

IMHO, Van's should change the nose gear to closely match the Bell tailwheel. See this pictures to get an idea of what I'm talking about.
 
Yes, a friend of mine touched down pretty level in his 6A (which means nosewheel first in a 6A) away from home (on pavement) and pretzelized his nose gear leg, luckily without getting his C/S Hartzell. Vans had a new leg to him via Fedex the next day. He borrowed some tools and a drill press and got it all buttoned up again with a valuable lesson learned.

6000 A model kits sold, 7000 nose gear legs sold. :rolleyes:
 
People have been knocking the nosegears off Cessna Cardinals, 182's, and 206's since day one, so an oleo strut isn't necessarily the answer. A stronger nose gear might help, but won't stop porpoising damage.

I think the grass strip failures will only be cured with a larger diameter nose
wheel. And then again, there are few justifications nowdays for building a tailwheel airplane besides grass and rough/soft fields. Maybe we could recognize this as a limitation for the "A".
 
Would anyone who has changed from the old to the new style nose fork care to offer an opinion as to whether this has increased the safety factor on rough surfaces? Are there any known cases where the new style fork (with it?s one inch extra clearance) has contacted/dug into the ground ?

Fin 9A
 
rv6ejguy said:
Yes, a friend of mine touched down pretty level in his 6A (which means nosewheel first in a 6A) away from home (on pavement) and pretzelized his nose gear leg, luckily without getting his C/S Hartzell. Vans had a new leg to him via Fedex the next day. He borrowed some tools and a drill press and got it all buttoned up again with a valuable lesson learned.
Click to expand...

Should RV's be designed so that they can tolerate all of the abuse they get from poor piloting technique such as this? :p

This is exactly the type of landing that also does in many of the certificated tricycle gear airplanes as mentioned by Yukon.

Seriously. This is very common at smaller narrow strips (as is common when a runway is grass). Spend some time just watching landings to a 2000 ft grass strip at a fly-in some time (not short I know, but it looks real short to most of the pilot population that is accustom to being able to fly sloppy landings at the 4000+ ft strips they mostly use) . You will see lots of flat landings with pilots forcing the airplane on the ground because they are quickly eating up runway because of excessive approach speed. This has caused many A model flip over accidents, including the one I am currently rebuilding (piloted by previous owner/builder).

As for this accident...I don't think much can be determined from the photos because there is a major break in info. between the first and the second photo.

I also find it very interesting that the first photo shows the elevators in what looks to be full up but the airplane is obviously running on the nose wheel (as already pointed out by Mel).
Not all flip overs buckle the fuselage as was the case here, so my guess would be that there was still a good amount of fwd. velocity when the flip over took place. If this is true, then there should have been enough elevator authority to hold the nose wheel off...Unless... (here is my arm chair quarterback guess)
The airplane touched down fast (meaning level attitude) just seconds before the first photo was shot and then the pilot was breaking hard while also applying full up elevator (even on grass this can keep the nose wheel pinned to the ground). Even with full up elevator this can put a lot more weight on the nose wheel than it would normally have which could have contributed to the accident. Not being able to see what happened between photo 1 and photo 2 makes it anyone's guess as to what actually initiated the flip over.
 
nose fork

If you look closely in the last photo you can see the nose wheel fork appears to be at a 90 degree angle to the bottom of the fuse. Glade they are ok.
 
Finley Atherton said:
Would anyone who has changed from the old to the new style nose fork care to offer an opinion as to whether this has increased the safety factor on rough surfaces? Are there any known cases where the new style fork (with it?s one inch extra clearance) has contacted/dug into the ground ?

Fin 9A
Click to expand...

Hi Finley,

We shared information back and forth after a parking incident flexed my nose gear leg back breaking my nose wheel fairing and gear leg fairing. Again, I can't overstate enough that this can happen at walking speeds! I was full back elevator and pulling into a tie down on grass and wasn't going over 2-3 mph. Witnesses tell me it was dramatic how much the leg bent backwards with the back of the wheel pant almost touching the bottom of the cowl. My gear leg went back to the OEM to get checked and cut for the new fork.

As to your question... I think the new fork should be a service bulletin or treated with similar language as was given to the fuel pickups being safetied. (Before further flight) There is an extra inch or so before the nut digs into the ground which is dramatic. I feel so strongly about it that if somebody needed my old one I wouldn't give or sell it to them. If you think you will ever operate on grass please do this upgrade. Besides being safer the fairing comes on and off much easier making it easier to service the bearings and replace tires. Also the way the brackets mount to the wheel fairing is much stronger.

I believe that people who operate on grass the majority of the time are going to be better than the rest of us at it, but I can tell you that a seasoned RV-A grass pilot wouldn't want to taxi their A model over the inocent looking hole that I hit. This hole didn't know if I had a lot of time or not. On the other hand though I'm not avoiding grass either. I have been back to the field many times where my problem happened. I know that I can keep the front end up and light and land that way every time whether on grass or the smoothest paved runways. Honestly the only time I think I'm at risk is when slow like turning on and off of the runway or parking.

Best,
 
Doug Reeves are you following this thread?

Doug, if you are following this thread my broken nose wheel fairing is at Grady's. When I got the new one all set up to paint Grady told me to send the old one and one day when they are slow they will patch it and paint it so that I have an extra. If you are down there visiting sometime you can photograph the front bottom so that people can clearly see how the bottom of the nose gear leg and the nut tried to tear thru the glass and dig into the ground. Just a thought... It is hard to imagine this happening but seeing is believing.
 
Skid plate?

Mornin' all,
A year or two ago, someone had posted some pictures of how they built up a lot of fiberglass from inside the point of the nosewheel fairing down to the bottom near the wheel opening. The thinking was that it acts like a skid plate if the wheel ever drops into a hole and prevents the sharp, lower fork edge from digging in since the thick part would be pushed against the lower fork. Anyone remember or have the link?

Thanks,
Pierre
 
Jock Strap

Friends of mine in Lockhart, TX. built what they call their "jock strap", a rounded steel plate covering the big nut holding the nosewheel fork on. Hopefully it will skid along the ground keeping the nut from digging in and prevent a tip over.
 
Look at the Grumman AA1/5 setup. There isn't any regular problem with them flipping over, yet they have a similar setup. It's all about execution of the design. Van's is simply a SPRING with no real dampning at all. This means it will flex up to a point, then bend. TO make it worse, it doesn't have enough ground clearance in the front pivot, due both to a poor design, and a too small tire.

Cessnas, Pipers and grummans all use 5.00x5 nosewheel tires, that helps out in these situations where you hit say, a small pothole. In an early -a model, that would be enough to flip you. In the current, it still gets your attention and a little deeper one can still cause problems.

Grumman's nosewheel leg has a dampner built into the fire wall and a couple of other details that escape me at the moment, but help contribute to stability.

Quick and dirty solution to the -a models? A 5.00x5 nosewheel fork.... with a new wheel fairing of course. Anyone interested in that kind of mod?
 
Finley Atherton said:
Would anyone who has changed from the old to the new style nose fork care to offer an opinion as to whether this has increased the safety factor on rough surfaces? Are there any known cases where the new style fork (with it?s one inch extra clearance) has contacted/dug into the ground ?

Fin 9A
Click to expand...
I'll second that. The fact that so many nosewheel airplanes have accidents like this is troubling. I am interested in a A model because of the simplicity of landing it and lower insurance - there's a reason why nosewheel airplanes are in the majority. However, this isn't exactly making the case for the A model. The good news seems to be that all of these accidents are survivable, but ....

osxuser said:
Quick and dirty solution to the -a models? A 5.00x5 nosewheel fork.... with a new wheel fairing of course. Anyone interested in that kind of mod?
Click to expand...
Yep. A larger nosewheel would help, but I suspect that the longer-term solution is a different design to the nosegear.

There is a lot of discussion about these accidents being caused by improper technique. Whether or not that is the case, I want an airplane that is somewhat forgiving. RVs are about performance, but if I spend all that time working on an airplane, I want it to be robust. The nosegear certainly seems to be a weak point.
 
The problem, as I see it, isn't that things break if you don't have good technique....it's that the plane flips and puts the occupants at risk. There's really no reason that the gear can't be designed with a couple of shear pins towards the top of the gear. Instead of tucking under and flipping the aircraft, the gear would simply collapse. Would that be better? I dunno...it'd be different and could possibly be a whole lot for the plane and the occupants. Could also make things worse.

Just throwing it out there...
 
agree, redesign might be called for but...

The Cessna 182 has a reputation for nosewheel damage too. In fact, after owning a few of these great heavy haulers and looking at many more over the years...I'm not convinced that MOST 182's have collapsed their nosegears over the years. I'll grant you most of these have not been while taxiing, but poor landing technique but nonetheless the failure rate of Cessna's HEAVY nosewheel arrangement indicates that shy of a major weight gain in the front end, it might be a difficult task to design much performance improvement (without a huge weight gain) for the -A models.
As others have said, technique plays a huge role in all of this...as does luck (we have the whole planet to land on and roll into a gopher hole or something similar). Sitting on the ramp watching "A-model" RV's land all day I am struck by the fact that about 75% of them put all three wheels on the runway at the same time...exactly what Mike Seager (and Van himself) preaches against. I think most (not all) of the nosewheel failures are rooted in excessive descent rates, too much speed on rollout and failure to keep the stick in the full aft position while taxiing.
 
As the builder of '96 (older) -6A, the photographs of the 7A tipping over are distressing. I could not find the video but here is what I see from the 4 photos.
The a/c is a later RV-7A which should have the upgraded nose gear leg and looks like it has the later nose fork.
A number of factors show that it was traveling at a very low groundspeed, i.e. multiple reference points in the photos, the way the props are bent, the proximity of the initial prop strike in the sod and final resting point, the fact that at the second photo both occupants have already braced themselves for impact, and that the impact vectors are almost completely vertical, being absorbed mostly by the dome of the canopy, which appears to have broken, and the roll bar, which did not fail, and which forced the longerons and fuselage skin to crumple. Furthermore, there is no apparent subsequent disturbed ground and the rudder position has not changed, which it should have, after impacting if the plane had slid. Also the primary point of failure appears to be the nose gear leg at a point just above the fork since it is bent a full 90 degrees aft, but the rest is not visible. So, my best guess is, the aircraft was taxiing at a relatively slow speed, was arrested by the sudden stoppage of the nose gear, and flipped over.
If this kind of thing is still happening since the new gear leg has been deployed, Vans needs to do a systematic review of the RV incidents involving nose gear failures, and, unlike some of the alternative engine vendors, who supposedly have not been admitting their problems, publicly disclose what the findings are. If not Vans, the FAA.
BTW, I have already bought the new beefier nose gear leg (U-603-2) which was $175 plus $40 freight. Now it looks like I will have to check out the new fork too.
Oh, yeah, and not land on grass when (if) my plane is built.
Dave A.
RV-6A
 
Missing Fairing on Nose Wheel

In the first photo, isn't the nose wheel fairing the white object under the right wing. I view this accident as landing with too much forward pitch and slamming the front wheel into the ground, causing the nose wheel fairing to fly off. That is what is shown on the first photo, I think.

Steve Anderson
RV 7A Finishing
 
You must log in or register to reply here.
Back
Top