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RV nose gear accident study results

N819VK said:
1500+ landings on grass in my RV-6A. .....I run 45 psi on all tires as it rolls noticably smoother with less power than a lower psi on grass. Am I concerned about my nose gear...NO.
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Well, I'll be darned, I'm not the only pilot flying with 45 psi.

I checked with Desser on tire pressure, the Air Hawk 5x500 6 ply is rated at 50 psi. The nose tire by Shin is not specifically listed but I believe it is rated at about 60 psi. Now I know Van's says 25 and 35 respectively, but so far 45 is working OK for me and I believe it is a suitable pressure for soft field ops. It maintains a better height between the surface and the bottom of the wheel pants, which get beat up much to much anyhow.

I agree with keeping it rolling after landing and I do it before take off also. By that, don't taxi real slow but taxi with enough power to keep the nose wheel light with aft stick and prop blast across the HS. It is very diffiicult to make a short turn taxiing slow but much easier going a bit faster with a light nose gear. We do a 180 at the end of one runway and this is the technique that works best. I do the check list after start on the pad at the hangar and if things work out, do not stop taxiing right up to lift off. Once you stop, the wheels settle in and it can be a chore getting it moving again, especially if it is a bit wet.

If there is a new rabbit hole, there's a chance the NG will bounce right over it with a bit of power on. Beyond that, we don't allow rabbit holes around here. There are a few coyotes in the territory and they keep such criters in check. I haven't seen a cat in six months, either. A greater risk is a wood chuck hole, they probably are not about to let a coyote get the upper hand. The only thing that keeps them in check is a 30-06. Many years ago, when things were a bit more normal than today, there was an old Captain out of ORD who carried a revolver in his crew kit specifically to controll airport jack rabbits at places like ABQ. He'd open the window and involk a bit of rabbit family planning for the benefit of other pilots and the traveling public. :)
 
loved the report

Citiing statistics certainly doesn't add anything, nor it it valid from an engineering sense.

What is striking about the report is the detail of the description of the flip-over mechanism - a sort of a "positive feedback" event. Once the nut touches the ground, the chain is set in motion. This has nothing to do with number of hours flown in any meaningful way.

Figure 18 of the photo section of the report describes how it only takes a 2G load (which isn't much of a bounce) and 70 extra pounds (a lot, but still not impossible), and 22 psi (low but not unthinkable) to guarantee ground contact, even with the new fork.

If you back off the weight to normal, and increase the tire pressure to 30psi, you get a whopping 1.37 inches of clearance. Doesn't seem like a lot, especially in a dynamic event.

Of course all the pilot technique comments are correct - they provide ways to reduce the dynamic load ("G") to prevent the positive feedback from starting. Good stuff, but I wonder if the design can't be improved simply.

The idea would be to improve the ground clearance, by at least another inch (an arbitrary number). Can an inch be shaved off the bottom of the existing gear (under the nut)? Probably not.

How about a new fork design, one that is a little longer and that angles down more steeply, and maybe even holds a larger diameter wheel? Even without the larger wheel I think you could get another inch of clearance. I guess the gear leg might have to be changed to preserve the overall ground attitude of the aircraft, or is an inch not going to make a difference? If it is just a new fork design, it could be used on existing gear legs? Just a thought - I hope some VAF mechhie designs one.

Also I thought the other dramatic thing is the amount of springiness in the NLG. It's incredible how far back it folds during the slide. Very good spring material.

I finally feel like I understand the flip-over mechanisim and that make me feel better about my "A" decision. I plan to include a nose wheel tire pressure check into my preflight. Every thing I can do to preserve that ground clearance will be done!

Great job to the NTSB - it's good to see the USG do something helpful. It's great to have real engineering data & analysis to read instead of some of the other stuff that people have been posting.

(I read the report too)
 
question about the report

In re-reading the report, I noticed the following on page 2 of the photo section:
Figure 18 shows a new fork design profile. The height from the ground to the strut is about 5 inches when the tire is unloaded. The threaded area in the drawing is extended about 1 inch to be consistent with the 4-inch ground clearance of the original strut and fork design.

Does this mean that Figure 18 is not the new fork?

Has NTSB taken a new fork geometry and extended the gear leg down 1.0 inch to mimic the clearance of the old fork design?

If so, I guess the clearances in figure 18 would be increased 1 inch for the new fork. Maybe the problem has been "solved" already.... Have there been any / many flips with the new fork?
 
new fork?

Dave, the drawing is of the new fork design. It would have about 5 inches of ground clearance. The extension of the strut threaded area on the drawing is one inch and represents the 4-inch ground clearance of the previous design.
 
New Fork/Old Fork ?

Several people have asked this, and I didn't see the answer as I read the reports...do we know for certain if all of the planes cited in the report were "old Fork" designs? That would be pretty significant....maybe it's there and I just missed it...anybody know the facts?

Paul
 
Latter then that.

AlexPeterson said:
I'm not sure when the design change happened, but it was somewhere in the 1997 vintage of finishing kits.
Click to expand...
I got my finish kit around the end of 2004 and it had the old style.

Kent
 
Additional Data

I'm not sure everyone is talking about the same changes??

It would seem that the additional data for each of the incidents would be useful:
- Original fork/gear leg versus new fork/gear leg (+1" additional ground clearance)
- Original axle/bearing design versus later axle/bearing design
- Nose wheel inflation pressure

And then harder to measure, assess, and a lot more greyscale in nature:
- Pilot experience (rollout & taxi incidents exempted?)
- Condition of the landing/rollout/taxi surface (hard/soft/wet/muddy/etc)
 
Discipline on posting

GrayHawk said:
I'm not sure everyone is talking about the same changes??

It would seem that the additional data for each of the incidents would be useful:
- Original fork/gear leg versus new fork/gear leg (+1" additional ground clearance)
- Original axle/bearing design versus later axle/bearing design
- Nose wheel inflation pressure

And then harder to measure, assess, and a lot more greyscale in nature:
- Pilot experience (rollout & taxi incidents exempted?)
- Condition of the landing/rollout/taxi surface (hard/soft/wet/muddy/etc)
Click to expand...

You are correct. This is a very important topic, and we must all read each post carefully when we respond. Frequently, there are posts which "refute" what was not actually said, or similarly, answer questions that were not asked.

I know of three independent design changes to the nose gear/wheel design:

1. Bearing retainer/axle design (a discussion of which is in another post I referred to earlier in this thread)
2. Nose gear strut modification (fatigue failure driven, IIRC)
3. Increased clearance fork.

Let's read carefully, the words matter.
 
Having just re-read the study I'm sitting here in amazement. The results are exactly in line with what my father-in-law and two of his friends described when I had my parking incident. Folks the NTSB nailed this! One of the things that stood out to me when looking at the report was that the tire pressure was unknown on my plane. Well the fact of the matter is that the old wheel pant mounting brackets were such a pain in the @$$ that the nosewheel had to be pulled in order to put air into the nosewheel tire. Pulling the cap off of the front of the nosegear fairing didn't allow enough room to check or add air and I hadn't drilled a large hole in the rear half of the pant to allow easy access. Because of this when I would finally go thru with this process the pressure was usually down around the 20psi range. I'd be willing to concede that the pressure was most likely in this range when I hit the tie down. Another thing that is noteworthy is my nose gear leg fairing was snapped at the top! This wasn't mentioned in the report possibly because they didn't know about it. I hadn't posted pictures of this broken item. Right where the gear leg fairing exited the intersection fairing on the bottom of the cowl the the gear leg fairing snapped from the bending way up at the top. This has been sitting in my hanger for a year and a half but just got tossed a couple of weeks ago. I wish I still had it so that a couple of more pictures could be shared. Another thing that seems crazy is the lack of any drop of the nose when my gear flexed back. From inside the airplane there was no indication that the trailing edge of my wheel pant almost hit the bottom of the cowl. There was a noise, but again no sensation that would indicate what had happened.

So now that some time has passed and the plane is back in form I guess having this happen was actually a positive experience. While it wasn't fun to have to upgrade to the new fork and mounting brackets for the wheel pant the plane is now better and safer for having done it. It also looks like posting the details helped at some level to get to the bottom of all of this.

Oh yea, I love my RV and I still land on grass.

Regards,
 
Bryan, thanks for having the courage to tell us your tire pressure was probably low. That's one problem all concerned can fix immediately. Yes, I know it's theoretically possible for a tire to deflate after preflight, but low pressure is a risk factor we can largely control.
 
Finally, some science

Craig, thanks for posting the NTSB results.
If you filter out all the emotional bravado, and the negative comments made on this thread, there is some really helpful info here on a number of things including good pilot technique. Also, finally some science and a real look at this issue.
I agree that the NTSB deserves strong commendation for their report. What they did took some hard work and analysis. It also clearly underscores a couple of things.
One, as is the case in a number of scientific disciplines, the experience of one individual, no matter how extensive (4000 landings on 2000 grass strips, etc.), may not always provide the correct information. You have to systematically look at a number of mishaps or events.
Two, this study definitely shows that there is a tendency, under certain conditions for the Van's designed nose gear to act in a seemingly predictable, negative way (notice I didn't use the word "problem"). Obviously, more analysis, and maybe finding other cases to examine, is needed, but hopefully, we can step away refusing to admit there is something going on with the -A nose gears and stop dismissing it as a lot of unskilled pilots out there. Perhaps the changes Vans has already made or the modifications suggested by other builders are all that is needed to make grass or unimproved strips more safe.
Dave A.
RV-6A QB
 
whirlpool said:
Bob has posted: the new series gear has not failed- where is the data to support this? Did I miss it?O.K. just my .02 please no flames needed!! ED
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The discussion continues thread after thread, but this is the real issue.....Has a mark II fork had an incident yet? I have asked the question repeatedly, with no one having knowledge of a confirmed incident.

It is difficult to produce data for the apparent absence of an event.

However I consider no news to be most definitely good news.

Until that point, complaining about the old (and clearly sub-optimal) design is pointless. Unless I am missing the point :confused: .
 
Amost certainly 100% record.....to date!!!

justinmg said:
The discussion continues thread after thread, but this is the real issue.....Has a mark II fork had an incident yet? I have asked the question repeatedly, with no one having knowledge of a confirmed incident.
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Justin, of course it's a very salient question.

It is thought that Vans designed the new MK2 fork (increased rake and clearance) in late 2004 and issued a bulletin on March 10, 2005, declaring that it was being shipped in Finishing Kits.

It might be expected therefore that there will be a reasonable number of RVs (presumably mostly QBs) that are now flying with the MK2 fork. A number of other flying pilots have chosen to retrofit it.

I have been monitoring the RVA nosegear collapse saga very closely for a number of years. Specifically I have monitored virtually all of the major RV forums including the RV Aircraft Builders Group, RVSQN (UK), VansAirforce, Matronics RV Group, RVs_in_Aus (Australia) and Rivetbangers.

To the best of my knowledge there has not been one report of a gear failure involving the MK2 nosegear. Many of the failures reported resulted in photos being published.....again, every published photo has been of a MK1 (old fork rake) nosegear.

The recent (famous for it's pix and video) Croft Farm accident was certainly a MK1 nosegear.

And all of the identifiable nosegears in the photos provided with the recent NTSB report are also MK1.

I would be confident at this stage that no MK2 nosegear has collapsed to date. I would be further confident that it will become public knowledge IMMEDIATELY that one DOES fail.....given the publicity surrounding this issue.

It is too early to draw firm conclusions on the improved action of the new fork, but the early indications are promising. Although there only a modest number out there, you can't do better than 100% success at this time. After all, as the NTSB report has clearly identified....ground clearance is the name of the game....and the MK2 has more of it....so it is logical that it should produce less 'dig-in' failures over time.

My only question is: Why didn't Dick VanG increase the rake, and therefore the ground clearance, even more than he did. After all, many free castoring designs have a significantly higher rake than the Vans MK2. I suspect he could have easily put at least another inch of clearance under the front nut without any problems. Actually, subsequent to the NTSB analysis, I suspect that he might now be thinking that too.
 
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First flight was 7/14/02 on my RV6A. It was also the first RV that I had ever flown in (not smart but unbelievable fun). On my second landing I over flared and basically stalled it some distance above the runway. After it was all said and done the G meter read 4 and the top of my head hurt but I was still standing on three legs. I've spent a lot of time on short grass strips and have had to use the breaks hard. I've had to fix my front wheel pant because I hit a shallow drainage ditch that the owner of a grass strip forgot to tell me about. I?ve land on very soft fields where it took ? power just to get it to start rolling after I stopped (looked ok from the air). I even landed with a flat tire (zero pressure) on the nose wheel. This was on concrete and I could tell something was not right. It did not pull to either side so I just gave it some power and drove it on the mains until I got as close to the turn off as I could. I now have 578 hours on the plane and based on my experiences as long as you don't bury the nose wheel in a whole to the point where the fork impacts the ground it's going to stay up.
 
mgaffney said:
First flight was 7/14/02 on my RV6A. It was also the first RV that I had ever flown in (not smart but unbelievable fun). On my second landing I over flared and basically stalled it some distance above the runway. After it was all said and done the G meter read 4 and the top of my head hurt but I was still standing on three legs. I've spent a lot of time on short grass strips and have had to use the breaks hard. I've had to fix my front wheel pant because I hit a shallow drainage ditch that the owner of a grass strip forgot to tell me about. I?ve land on very soft fields where it took ? power just to get it to start rolling after I stopped (looked ok from the air). I even landed with a flat tire (zero pressure) on the nose wheel. This was on concrete and I could tell something was not right. It did not pull to either side so I just gave it some power and drove it on the mains until I got as close to the turn off as I could. I now have 578 hours on the plane and based on my experiences as long as you don't bury the nose wheel in a whole to the point where the fork impacts the ground it's going to stay up.
Click to expand...
Sounds like you've been extremely lucky, but I wouldn't bank on that continuing if you push the odds like you've been.
 
PLEASE...

I am really enjoying the discussion about potential modifications to the nose gear design that might improve safety margin. Can we please reserve this thread for that purpose??? I would really hate to see it morph into yet another "taste great, less filling" debate about pilot error vs. design problem. So, PLEASE, if you want to argue that point, use one of the other umpteen threads or create your own new one.


Thanks,
 
Van at Oshkosh & the A Model Study

Will some of you lucky folks going to Oshkosh see if you can find out if Van is looking at any changes to the nose gear since this NTSB study is now out? I have the original 7A gear and plan to go to the new current setup but I think I'll wait a few months to see if anyone finds the golden fix or Van makes another change! I'm working on my windshield and will be hanging the engine on it soon. Wiring and avionics are finished so it's starting to look like an airplane! Yahoo!

Danny
N625DB
 
3 points

Went to Van's Homecoming and witnessed many 3 point landings by trikes... yikes. :eek:

NTSB report stated 370 lb empty nosewheel weight and bad things happening at loads over 1,000 lbs... a 3G landing on the nosewheel. :(

Surely we can all do better than that.

Invest in transition training.
 
Expedition E350 nosegear

For those of you who get the "Pilot Getaways" magazine there is an interesting picture of the nose gear of a plane called an Expedition E350 in the July/August 2007 issue. In fact there is an entire article about the airplane and how rugged it is. The E350 is a 4 place high wing with a free castoring nosewheel that looks very much like our "A" model right down to the gear leg fairing and wheel pant. What caught my eye is a picture on page 28, picture number 3. The motor mount has a linkage built into it with a shock absorber consisting of rubber doughnuts much like the ones in Mooney main landing gear. There is a pivoting or sorts that can happen to absorb loads. This plane is being marketed for its ruggedness and back country capabilities leading me to believe there is something to this design for the nosegear. It looks like a simple and light solution to some of the accidents or incidents and wouldn't be crazy expensive to undertake.

Expedition does have a web site, http://www.expeditionaircraft.com/ but there were not any photos of the nose gear when I looked a few weeks ago. But for those of you with the magazine what do you think? Could this somehow help us? :rolleyes:

Blue skies,
 
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Weak nosegear?

I'm not sure how similar of a nosegear this is, but below is a picture of the PulsarXP I recently owned. Note the very small nosegear leg. I always got questioned by people on the ramp about how sturdy it was. I believe it was 3/4" diameter solid steel tube, but it had a shock absorber at the top that allowed it to pivot forward.

Funny thing is, this gear didn't have problems but builders were always worried about its appearance and actually added fairings or (as in the 2nd picture below) glued balsa to the aft side to make it appear bigger.

I know it's a lighter aircraft and all (1100 lb gross), but it's also a smaller gear leg. I think the fact that the shock absorber was there helped a lot. I made plenty of crappy landings in the beginning, and the fellow I sold it to made plenty of hard 3-pointers, too. It's held up on lots of Pulsars for the last 15-20 years.

Sorry if this isn't an apples-to-apples comparison...I just wanted to point out the use of the shock absorber.


picture004.JPG


Rockshoc%201.JPG
 
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I spoke to Vans at Oshkosh

I quietly walked up and started talking to Tom outside the tent when he was catching a breath of cool air. I asked about the NTSB study and he said they, Vans, asked the NTSB to look at the nose gear. He said they check the NTSB reports every day to see if anything happened to one of their planes. He said that they concluded that it was improper piloting that was causing the problem and said the NTSB was satisfied with the design. I don't think they are going to do much to change it. I can't help but wonder if another fork with even a steeper down angle and therefore more clearance wouldn't help. I may get some of my mechanical engineers at work to do some modeling.

Paul
N694BP Reserved
RV-6A
 
Landing Van's A Models

I had the pleasure of flying with Dave Austin for transition training in Denton Tex. I mentioned that I wanted to go into a grass strip but all the forum BS was making me wonder. His take was refreshing and backed up with his teaching in a 9A. Pilot training is the key. We landed 17 times on grass and small asphalt runways and he taught me to land on the mains and keep the weight back until the plane slowed down to a crawl. This requires using the rudder to control the plane much like a tailwheel landing. One technique he espoused was bringing up the flaps on roll out and with the nose wheel still in the air. This ensures further speed reduction and the nose wheel makes contact with the ground at the lowest possible speed and with the least force.
 
Good 'ol Dave

Dave Austin gave me a lot of my primary training (in his C-150) back in the 80's. I solo'd in his plane - N1674Q....you never forget the tail number of your solo plane <g>.

What a great guy (and good instructor). I'd trust whatever he says.

b,
dr
 
Great on nice days

Steve A said:
We landed 17 times on grass and small asphalt runways and he taught me to land on the mains and keep the weight back until the plane slowed down to a crawl.
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Yeh, I did the transition training with Mike Seager....same thing...stick all the way back until the nose gear plops down. It's great training and good fun...on the nice days that are conducive to a bit of flying finesse.

Then there's the ugly days....rain beating on the windshield...can hardly see the edge of the strip...strong cross wind and sudden gusts. That's when you may not be able to do the "pull-the-stick-back-progressively-and-plop-the-nose-down-gently" trick. That's when we'll all be praying that the nosegear holds up. :confused:

As they say in the classics....you're only as good as your LAST landing (actually I made that up !) :)
 
Captain Avgas said:
Then there's the ugly days....rain beating on the windshield...can hardly see the edge of the strip...strong cross wind and sudden gusts. That's when you may not be able to do the "pull-the-stick-back-progressively-and-plop-the-nose-down-gently" trick. That's when we'll all be praying that the nosegear holds up.
Click to expand...

Hmmm... It's been a long time since I did my primary training, but while working on short field and soft field procedures I don't remember my instructor every saying "do this if you are able too", "If you are not to tired", etc., etc.

With the large number of certificated aircraft that get nose gear related damage every year, I guess there are a lot of "ugly days" for pilots. ;)
 
Captain Avgas said:
Yeh, I did the transition training with Mike Seager....same thing...stick all the way back until the nose gear plops down. It's great training and good fun...on the nice days that are conducive to a bit of flying finesse.

Then there's the ugly days....rain beating on the windshield...can hardly see the edge of the strip...strong cross wind and sudden gusts. That's when you may not be able to do the "pull-the-stick-back-progressively-and-plop-the-nose-down-gently" trick. That's when we'll all be praying that the nosegear holds up. :confused:

As they say in the classics....you're only as good as your LAST landing (actually I made that up !) :)
Click to expand...

I've found that landing at night can increase the probability of a less-than-perfect landing. Precise depth perception is a problem. To counter, I keep a little engine rpm on until just touching down. No short fields for me a night, though.

Also, on those gusty cross wind days, full flaps can be too much and the light little RV can get pushed around. Half flaps works well.

Flying in the rain at $4.50/gallon? :eek:
 
Vans A Flipping

I am posting a link a friend sent to me... only because it clearly shows an a model RV on grass flipping at somehting like 10-20 mph. It appears to me the nose gear gets a small bounce, mains on solid and then the whole plane just flips. Seems like clear evidence to me of a situation that should not occur, even if the pilot had applied braking, etc b/c the plane appears to be below the speed at which the pilot was able to hold off the nose.

Whadda yall think?

http://www.liveleak.com/view?i=c7b_1189120813

Bryan
 
bryanflood said:
Whadda yall think?
Click to expand...

I think you're coming a little late to the discussion.. :p

That incident is pretty much what started all of the current round of nose wheel types flipping - for more reading, do a search on "nose wheel", get yourself a favorite beverage and settle in for some long threads.... :D

Paul
 
I'm not trying to start an argument but... Im building my tail and plan to do the 7a but this has got me concerned. At first this issue seemed to me to be pilot error. Peter pilot just wanted to let the nose drop to soon, found a rut and over she went. However giving the NTSB report an open minded look, I don't think that?s always the case. They stated 1-2k on the nose and over she goes and the gear actually helps spring her on her back!!! Some of the nose collapse reports happened at very slow speeds. Some so slow there?s no way you could keep the nose in the air. Also some on "washboard concrete". Which makes me think back and talking about the nose springing fore and aft during taxi and how ?That?s the way it is?. All gear moves. Even on our big expensive planes you can wiggle the mains a little when their on jacks. But there are limits. This to me seems like ... not design error but rather not enough room for error built into the design. It seems things have to be just like they where in the lab or else. If I put $70,000.00 and a lot of me time into a plane I had better not have to worry about flipping over during a slow taxi.:confused: Like I said I'm not trying to argue but this is a significant investment and I'm just wanting to know if you guys are feeling my concern or am I missing something and acting like a worried mother. :eek:
 
jury still out

Mark: I fly a 9A mostly on paved runways, although I have landed at a couple of really rough fields. One before I knew better and one recently on a field that had not been maintained since the last time I was there. I made a hot landing and kept the nose off for as long as possible. When it came down, I thought to myself, you just broke your airplane. I kept waiting for the nose to dig in. Kept back pressure, tried to stay off the brakes and it rolled to a stop. Upright. I taxied to the parking area while holding my breath bouncing along in the tall grass holding the stick back hoping I wasn't pulling so hard it would bend. When I took off I promised myself that I would not come back there.

With that said, we have all read of similar situations that ended up, downside up or bent gear legs. I'm not a better pilot than those that broke or went over. There could be many reasons, maybe, I luckily didn't hit the worst spots on the poorly maintained field, nosewheel tire pressure was good, light engine prop combo, sufficient clearance between fairings and tire, breakout pressure correct on nosewheel fork, and other stuff that I can't think of, or a combination of all these things.

Maybe there are some nosegear legs that have weaknesses that haven't been ID'd yet.

I also forgot to mention that I have the old style nosegear fork with less clearance. I plan to do the SB fix to get the extra inch of clearance at my next annual in March.

While there have been several of these accidents that looked like everything was done right, I'm not sure if they were using the new style fork. That would be interesting to know. I don't know how to reassure you, other than for every incident/accident there are a few hundred A models with hundreds of hours flying, landing and taxiing right side up.

I for one love the A models for the ease of landing and actually like the look better also.
 
When I was completing my -7A in early the spring of 2005, I was looking for guidance on tire inflation recommendations. At the time this document addressing "Nosewheel shimmy" was available on Van's website:

It seems that Van's might have brought some of this nose gear angst on themselves by advocating nose wheel tire pressures as low as 20 psi. There could be as much as a 1" difference in height above the surface between the 20 psi tire pressure that I first flew with and the 35 psi that I use now. After 270 hrs. on the plane, I'm comfortable with the existing setup as long as I keep the nose tire pressure up where it belongs.

The plane survived the "death taxi" at Oshkosh this past year and apparently every other plane did, too, because no one nosed over there. That was a good enough test for me!!

Mike
 
I've been thinking (dangerous, I know). I recently determined that I was dragging my brakes a lot. The fix was to build up the rudder pedals so that I don't ride the brakes during taxi, takoff, or landing.

It's a major improvement. Before, I noticed that unless I slide my feet onto the side of the rudder pedals, the nosegear would come down on landing, and now it's easy to keep it off for the entire rollout. Also, my takeoff distance has improved. I also wore out a set of brake pads by 150 hrs.

Could it be that one of the contributing factors is dragging brakes causing pitching moments? This would effect all phases of taxi/takeoff/landing and might contribute to nose-overs. This would have more of an effect at low speeds when the elevator is not effective.

It might explain why some folks never have a problem in rough field conditions, while others fold the gear during taxi. When maneuvering on a soft field, inadvertant brake actuation could explain why the nose gear is digging in.

Personally, I think its a contributing factor. I've fixed the problem and I keep 35 psi in the nose wheel and I built a skid plate. Next step is the new fork/gear leg.

V
 
50 hrs on my 9A

I just passed 50 hrs on my 9A. I live on a grass strip. I use lots of trim on landing and always keep the nose light. So far no problems!

Joe Ramotowski
N358JR
RV9A Slow build
 
alcladrv said:
SNIP

The plane survived the "death taxi" at Oshkosh this past year and apparently every other plane did, too, because no one nosed over there. That was a good enough test for me!!

Mike
Click to expand...

Unfortunately, I believe a 9A went over, I don't know the situation, but recall hearing about it while I was there.
 
vlittle said:
... The fix was to build up the rudder pedals so that I don't ride the brakes during taxi, takoff, or landing.

It's a major improvement. Before, I noticed that unless I slide my feet onto the side of the rudder pedals, the nosegear would come down on landing, and now it's easy to keep it off for the entire rollout.
Click to expand...

I've been trying to be very aware of not depressing the brakes unless I need to, but perhaps because of the design of the pedal, I inadvertently get brake when I am depressing the rudder.

Can you explain how you "built up" the rudder pedals? Thanks.
 
One way to minimize depressing the brake pedal

Fly without shoes. Better sensitivity of where your footsies are.
 
Mike S said:
So, is there anybody out there using these??

http://www.cleavelandtool.com/filecab/RVSGPedal_Brochure.pdf

If so, how do you like them???

Are they worth the $$$$??

Thanks.
Click to expand...

Looks like they might work because they project the rudder pedal aft quite a bit more. I think they assume that you have small feet, though. With my heel on the floor, my toes can actuate the brakes. Size 11 feet.

Gee, I should sell my laminated hose fix for $100. Half the price of the cleaveland parts and easy to install!

V
 
Look good to me

I think they look like an improvement over the Vans standard pedals. There may be a weight penalty. I like the looks of them and think they would help prevent inadvertant braking. Now the cost....??? seems a little on the high side. Back when I was still building and still had some money in the account, and knew then what I know now, I probably would have bought them.
 
I think a piece of rubber hose, slit, and placed over the lower bar would work just fine. When I built my RV, I just pitched the brakes forward a little. I have AL skid plates under the pedals and just make sure I have my heels on them during TO and landing.

Roberta
 
Build9A said:
I think they look like an improvement over the Vans standard pedals. There may be a weight penalty. I like the looks of them and think they would help prevent inadvertant braking. Now the cost....??? seems a little on the high side.
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I agree totally.

I was hoping someone out there had bought them, and could report on how well they actually work.

Looking at the design, it looks like the lower pad is located so that it actually applies pressure that retracts the master cylinder, good if you have a sticking unit.
 
RV Flip Overs

Our solution at Lockhart, Texas, to the RV 6, 7, 8 & 9-A nose wheel fork plows and subsequent roll-overs was to install a skid plate to protect the nut at the bottom of the fork. A well-known RV Guru at Lockhart thought of it and welded one together for me. The flat face of the fork with a big nut sticking below it does not make a good plow. Even if the fork is presently rounded and sets an inch higher, as of February, 2005, it still does not make a good plow. A rounded, metal skid plate behind the fiberglass cup of the front wheel pant does offer protection--especially if that cup has 3 layers of fiberglass on the inside leading edge of it. The 3-layer is rock hard and fits snug against the skid plate and does not allow a gap between the skid plate and nose cap. If the nose cap is put on while the 3-layer is still wet, it forms to the skid plate. Any gap will allow an impact to crush the fiberglass and thus expose the fork and bottom nut so they dig in. Then the strut will bend back and collapse. The one-inch higher fork may or may not solve the problem. The concept is too new to provide statistics one way or the other. I have 480 hours on my RV-7A with over half of that using the skid plate. Don't get me wrong, I plan on doing the "Mandatory" Service Bulletin; but I'll be also pulling off the "jock strap" and moving it to the new fork for extra insurance because I'm convinced it has saved my RV-7A and my bacon more than once. I enjoy fly-ins to out-of-the-way places like Reklaw where you land on uneven dirt strips. I intend to keep flying into places like that.
 
I installed an antisplat reinforcement on my 7A and I would have to say that i noticed no difference taxiing or otherwise what so ever. However, I will say it made me feel more confident just knowing the device was there. I wonder if anyone has tried engineering the heavier RV 10 nose folk to suit a 6 or 7 . The 10 dosent seem to have the nose wheel coloapse problems of the two seat models, or at least I havent heard of any at this point.
 
Paul Walter said:
I I wonder if anyone has tried engineering the heavier RV 10 nose folk to suit a 6 or 7 . The 10 dosent seem to have the nose wheel collapse problems of the two seat models,
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The 10 uses a totally different system for the nose gear leg than the two seat models.

On the two seaters, the nose leg flexes to provide the spring action. The 10 uses a rigid leg, that pivots at the upper end, and a stack of rubber discs as a compression spring.
 
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