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-   -   New "A" Nose Gear - Should I Update? (https://vansairforce.net/community/showthread.php?t=173820)

LeonardWestermeyer 08-02-2019 10:35 PM

Pictures of New Gear Kit
 
Hi all,

Here’s a link to some photos of the new Nose Gear Kit for the RV-7A. I’ve included photos of all the accessories included, drawings, etc. Also a picture of the parts laid together with the donuts in place.

https://photos.app.goo.gl/q1z8DSJJgxMkHbm1A

There’s a lot more engineering involved here than in the original gear, so the cost begins to be justified.

Hope this helps the undecided.

Leonard Westermeyer
RV-7A “almost” completed.

dreed 08-02-2019 11:49 PM

Thank you Leonard!

Very nice looking mount. Anxious to get my hands on mine!

One question- what is the blue (alu?) bolt for?

Capt 08-03-2019 05:15 AM

Quote:

Originally Posted by LeonardWestermeyer (Post 1363834)
Hi all,

Here?s a link to some photos of the new Nose Gear Kit for the RV-7A. I?ve included photos of all the accessories included, drawings, etc. Also a picture of the parts laid together with the donuts in place.

https://photos.app.goo.gl/q1z8DSJJgxMkHbm1A

There?s a lot more engineering involved here than in the original gear, so the cost begins to be justified.

Hope this helps the undecided.

Leonard Westermeyer
RV-7A ?almost? completed.


Gee that's a vast improvement to the weak original design. Top job Vans, they obviously know the A models need 'attention' :)

jcarne 08-03-2019 07:53 AM

Quote:

Originally Posted by LeonardWestermeyer (Post 1363834)
Hi all,

Here?s a link to some photos of the new Nose Gear Kit for the RV-7A. I?ve included photos of all the accessories included, drawings, etc. Also a picture of the parts laid together with the donuts in place.

https://photos.app.goo.gl/q1z8DSJJgxMkHbm1A

There?s a lot more engineering involved here than in the original gear, so the cost begins to be justified.

Hope this helps the undecided.

Leonard Westermeyer
RV-7A ?almost? completed.

Thanks for posting the pics Leonard, there is a lot more parts to it than I thought.

jcarne 08-03-2019 07:54 AM

Quote:

Originally Posted by LeonardWestermeyer (Post 1363834)
Hi all,

Here?s a link to some photos of the new Nose Gear Kit for the RV-7A. I?ve included photos of all the accessories included, drawings, etc. Also a picture of the parts laid together with the donuts in place.

https://photos.app.goo.gl/q1z8DSJJgxMkHbm1A

There?s a lot more engineering involved here than in the original gear, so the cost begins to be justified.

Hope this helps the undecided.

Leonard Westermeyer
RV-7A ?almost? completed.

Thanks for posting the pics Leonard, there is a lot more parts to it than I thought.

eric.the.blonde 08-03-2019 10:39 AM

Andy,

I intend to go with the newer solution. The original design was revised at some point to give more clearance to the nose fork. Since you have a low serial number, if you do not yet have the parts for SB 07-11-09 then the upgrade is a no-brainer. A lot of people believe in some of the aftermarket solutions for the original nose gear design, I haven't seen one that I would install.

LeonardWestermeyer 08-03-2019 11:03 PM

Axle Improvement on New Nose Gear
 
In answer to Dan Reed’s question about the blue aluminum part shown in the photos of the new Nose Gear Kit, I have investigated and have some really good news to report!

As you probably know, one of the problems which contributed to the failures of the original Nose Gear was the difficulty in the adjustment of the axle torque. The conical bearings were adjusted with the same bolt which torqued the wheel in the fork. If this bearing torque was incorrect or was affected by a rough landing or uneven landing surfaces, it could cause the bearings to freeze up and provoke the collapse of the gear.

Currently there are two solutions to this problem. One offered by the Anti Splat company for $234 which replaces the conical bearings with sealed ball bearings and includes a spacer between the bearings to permit the axle to be tightened to the fork without affecting the bearing operation.

The other solution is offered by Matco, the manufacturers of the wheel, and for $80 adds an internal axle on which the conical bearings are mounted. The internal axle has an adjustment nut with its own locking mechanism to allow the bearing torque to be adjusted independently from the main axle bolt’s torque on the fork.

The good news is that this Matco solution is included in the new Nose Gear kit!

I will include a link to the old and new C1 drawings where you can see the modification:

https://photos.app.goo.gl/yV2NyjyNVsViJn6p8

Leonard Westermeyer
RV-7A in “final” stages of construction

rvbuilder2002 08-04-2019 12:28 AM

Quote:

Originally Posted by LeonardWestermeyer (Post 1364032)
The good news is that this Matco solution is included in the new Nose Gear kit!

The axle assembly shipping with the new nose gear /engine mount is a Van?s designed and manufactured part.

LeonardWestermeyer 08-04-2019 01:32 AM

Axle Manufacturer
 
Sorry for the misinformation.

It does appear to be a similar solution to the Matco part, although I think it?s probably superior in the design of the locking mechanism.

Anyway, super happy with the solutions which will help us to sleep better!

Leonard Westermeyer

Walt 08-04-2019 06:15 AM

My choice for a nose wheel is the Beringer, plus it's tubeless:

KazooRV-9A 08-05-2019 11:54 AM

So I made a call today to Van?s. The upgrade nose gear is $3225.00 plus shipping, since I haven?t yet drilled for my old (WD-739-PC) mount.
They will not offer a trade for my old mount (and front leg), as they are more than 2 years old. There?s no mechanical difference to a current 739 mount or 603 leg, they?re just beyond a date chosen by Van?s. If they were less than 2 years old, they would offer $750 in trade.
The parts gal indicated that they are into mid-September for shipments of the rev A gear.
Current price for a new ?Old? 739 mount is $1200, and new old 603 leg is $267.50.
Seems like there?s going to be a bunch of original design mounts and legs available out there, so selling them to offset the cost of the new A front may not be a significant help.
What to do now...
More thoughts?

wirejock 08-05-2019 12:40 PM

Value
 
Quote:

Originally Posted by KazooRV-9A (Post 1364364)
So I made a call today to Van?s. The upgrade nose gear is $3225.00 plus shipping, since I haven?t yet drilled for my old (WD-739-PC) mount.
They will not offer a trade for my old mount (and front leg), as they are more than 2 years old. There?s no mechanical difference to a current 739 mount or 603 leg, they?re just beyond a date chosen by Van?s. If they were less than 2 years old, they would offer $750 in trade.
The parts gal indicated that they are into mid-September for shipments of the rev A gear.
Current price for a new ?Old? 739 mount is $1200, and new old 603 leg is $267.50.
Seems like there?s going to be a bunch of original design mounts and legs available out there, so selling them to offset the cost of the new A front may not be a significant help.
What to do now...
More thoughts?

I considered the value lost as part of cost. No way I will get $1400. I might get 1/2 of Vans $750 someday but I doubt it. Hurts but I like the added peace of mind and so does the better half.

KazooRV-9A 08-05-2019 02:04 PM

So by that thought, the sunk cost is upwards of $5K, if you already have bought your FF kit...
Are my chances of folding my original equipment nose gear that great?
Are there any published statistics on nose gear damage per flight hour on 7?s and 9?s?
And there?s no actual data yet on the Rev A mod field performance, for me to use for peace of mind. Revised hardware can have different effects.
I can?t get past the cost issue, with no data. I?ll grant you it looks more impressive and complex.

dreed 08-05-2019 02:05 PM

I'm with Larry-

The old mount/leg are sunk costs. If I ever get something out of the... great. If not, I'll just just make coffee at home more often vs. getting at a shop.

gmcjetpilot 08-05-2019 04:25 PM

Quote:

Originally Posted by KazooRV-9A (Post 1364384)
So by that thought, the sunk cost is upwards of $5K, if you already have bought your FF kit...
Are my chances of folding my original equipment nose gear that great?
Are there any published statistics on nose gear damage per flight hour on 7’s and 9’s?
And there’s no actual data yet on the Rev A mod field performance, for me to use for peace of mind. Revised hardware can have different effects.
I can’t get past the cost issue, with no data. I’ll grant you it looks more impressive and complex.

You make great points. If you're not close to installing the engine mount and nose gear you can wait. I don't know what the lead time is on it.

As far as statistics nothing official. If someone's willing to do the research they could probably come up with rough numbers. Considering how long RV A models have been out there, a vast number of them flying, relatively few incidences, the original design seems satisfactory? Up to you. It's not robust but its weaknesses can be mitigated. Soft field landings on uneven surface is not its strength.

As far as the new one it looks heavier and maybe more drag? Can it have unknown issues itself? Won't know for years to come. You can always build it original and fly. Later then you can retrofit it if you choose, but that seems like a lot of extra work.

If you fly off hard surfaces, land properly, have well-balanced tire/wheel, modified bearings, anti-splat devices your chance of a problem seems remote. If cost is issue the choice seems obvious.

Kyle Boatright 08-05-2019 04:47 PM

Quote:

Originally Posted by gmcjetpilot (Post 1364409)
As far as the new one it looks heavier and maybe more drag? Can it have unknown issues itself?

Unknown? Here's one:

What will all of that revised (additional?) structure down near the base of the firewall do to the cooling outflow?

RV8JD 08-05-2019 05:09 PM

Quote:

Originally Posted by Kyle Boatright (Post 1364415)
Unknown? Here's one:

What will all of that revised (additional?) structure down near the base of the firewall do to the cooling outflow?

Scott M (rvbuilder2002) posted that the goal of the new "Cowl Louver Kit" was to improve cooling during climb with the new nose gear assembly.

Weight and CG effects were addressed in the SL announcing the new nose gear mod, Service Letter 19-04-30.

What hasn't been addressed to my knowledge, is whether Van's has, or will, give some relief to their published weight-on-nose-wheel limits, given the heavier new nose gear mod and its forward shift of the CG. See this post: http://www.vansairforce.com/communit...3&postcount=19

jcarne 08-05-2019 05:33 PM

Quote:

Originally Posted by RV8JD (Post 1364420)
Scott M (rvbuilder2002) posted that the goal of the new "Cowl Louver Kit" was to improve cooling during climb with the new nose gear assembly.

Weight and CG effects were addressed in the SL announcing the new nose gear mod, Service Letter 19-04-30.

What hasn't been addressed to my knowledge, is whether Van's has, or will, give some relief to their published weight-on-nose-wheel limits, given the heavier new nose gear mod and its forward shift of the CG. See this post: http://www.vansairforce.com/communit...3&postcount=19

It was "addressed" at Airventure in a method that a detective had to deduce. haha :D

This pic is a screenshot of a picture John Bright posted from the QB kit with the new mount at Airventure. Read the second line from the bottom. So it seems to me that the engineers at Vans seem to find this new system to be stronger.

Capture by Jereme Carne, on Flickr

RV8JD 08-05-2019 08:42 PM

Quote:

Originally Posted by jcarne (Post 1364426)
It was "addressed" at Airventure in a method that a detective had to deduce. haha :D

This pic is a screenshot of a picture John Bright posted from the QB kit with the new mount at Airventure. Read the second line from the bottom. So it seems to me that the engineers at Vans seem to find this new system to be stronger.

Capture by Jereme Carne, on Flickr

I'm glad they noted it somewhere. Now they just have to revise their published "weight-on-nose-wheel limits" Service Letter to reflect that there are no nose wheel weight limitations if the new NG mod is installed.

Thanks for the info!

RV10inOz 08-06-2019 03:44 AM

Land at the correct speed.

Use the MAIN gear like you should.

I am convinced this is a solution to a non problem. Except those who refuse to fly properly.

Give them stronger gear they will shift the resultant forces elsewhere from their bad piloting.

I may be wrong, but lots of RV's operating off a rough strip at my home field would suggest it is not the product design that is the problem.

And yes, two recent wrecks here in Australia just prove my theory. They were not the fault of the design.

Happy to take flack, but you will need a good argument because low experience pilots flying properly do not have a problem on rough strips.

Capt 08-06-2019 05:22 AM

I guess at the end of the day it's all about choice. A model drivers now have a choice.
What 'price' do you put on safety? That's an individual thing!
Vans obviously know the original design is weak otherwise there wouldn't be choices!

Gabe 08-06-2019 05:31 AM

Original nosewheel still pretty tuff
 
I've been following this thread with interest and would like to share my experience with my take on this. I had and still have the original nose wheel design on my 7 and experienced a nose over trying to land on an unfamiliar grass strip 1200 feet long on my last leg of phase 1 testing. My approach speed was way too high.. 80Kts.. floated and landed deep.. i should have gone round but because of the uphill landing i felt that i would make it, needless to say my nose went over the edge of the runway at approx. 5 knots and dropped about 20 feet thereby nosing over. i had the anti splat nose mod brace installed and after the event it became evident that the brace does work pretty well and that the original design is pretty strong. As others have said if one flies the nose wheel version of these amazing planes, keep the weight off the front as much as possible and fly them as it's design intends. After the repair work i went back to the said field and landed with a just under a half length remaining.

Gabe 08-06-2019 05:43 AM

Original nosewheel still pretty tuff
 
Added some images


eric.the.blonde 08-06-2019 06:41 AM

Quote:

Originally Posted by Capt (Post 1364489)
Vans obviously know the original design is weak otherwise there wouldn't be choices!

Rubbish. These forums are filled with emotional, data-lacking entries about the nose gear. A good engineer knows to ignore uninformed, emotional "advice". A marketing person might have to whisper into the engineer's ear abut a PR problem and it may take a while to get the engineer to sign up to the business case...

I've not seen any data that improves on the 2007 NTSB study about the old design.

Oh, and by the way I hesitate to call the new design an improvement until I see the data. While I do like the notion of the new elastomers more effectively converting spring energy into heat, I don't KNOW that it is BETTER. I only have an analogy to guide me: it is unimaginable to drive my car without it's shocks converting spring energy into heat.

YellowJacket RV9 08-06-2019 07:01 AM

Quote:

Originally Posted by Capt (Post 1364489)
Vans obviously know the original design is weak otherwise there wouldn't be choices!

No, Vans knows there?s a market for choices. Plenty of products are available in various choices depending on use case:

Light duty vs heavy duty pickup truck
iPad Pro vs iPad Air
Tylenol vs extra strength Tylenol

The availability of a stronger option doesn?t mean the other one is weak. It simply isn?t optimized for the type of flying some people do, and/or their technique. The original gear has proven that it is perfectly capable in the VAST majority of cases. If I were planning on a lot of rough field ops, I?d upgrade. But I?m not, so I won?t. And I also appreciate that Vans isn?t forcing the upgrade on people, thus allowing those who don?t see the need for it to save a not-insignificant amount of money.

Chris

KazooRV-9A 08-06-2019 07:29 AM

"What price do you put on safety"
I am a retired Aerospace Engineer with 40 years in the aircraft industry working for a major industry supplier, in product development Engineering.
I doubt seriously that Van's would state that the original design is unsafe or has any severe shortcomings. And shouldn't, given the number of the current design in service and the overall hardware history.
My point is that there is no data yet to support that the revised design will reduce front gear damage incidents in the -7A and -9A models. Simple fact, it's new on the market.
You can't simply look at a design and determine it's relative effectiveness. While the new design may perform better in a drop test, and has improved FEM results under some selected analytical load conditions, drop is only one type of load. Whether it would reduce failures in actual field use (complex loadings), is not yet known. I'd love to review the stress analysis.
It appears that Van's is taking the opportunity to adapt a later nose gear from heavier aircraft, to other current models. This has some trades (weight/drag/cooling flow/cost/lead time/assy time). If I've seen anything over my years at work, it's that every design change has an effect. I see it as intending to have greater margin for adverse landing loads. I applaud Van's for this evolutionary goal, and of course their marketing dept. is also hard at work with it, as they should be.
However.... If I choose not to incorporate the revised design, I'd hate to think that I am significantly risking my safety!

RV8JD 08-06-2019 04:17 PM

Quote:

Originally Posted by Gabe (Post 1364494)
I've been following this thread with interest and would like to share my experience with my take on this. I had and still have the original nose wheel design on my 7 and experienced a nose over trying to land on an unfamiliar grass strip 1200 feet long on my last leg of phase 1 testing. My approach speed was way too high.. 80Kts.. floated and landed deep.. i should have gone round but because of the uphill landing i felt that i would make it, needless to say my nose went over the edge of the runway at approx. 5 knots and dropped about 20 feet thereby nosing over. i had the anti splat nose mod brace installed and after the event it became evident that the brace does work pretty well and that the original design is pretty strong. As others have said if one flies the nose wheel version of these amazing planes, keep the weight off the front as much as possible and fly them as it's design intends. After the repair work i went back to the said field and landed with a just under a half length remaining.


Here are some of your pics. I hope you weren't injured.






Captain Avgas 08-06-2019 07:21 PM

Quote:

Originally Posted by eric.the.blonde (Post 1364514)

I've not seen any data that improves on the 2007 NTSB study about the old design.

Oh, and by the way I hesitate to call the new design an improvement until I see the data.

Interesting comments from someone who in Post #46 said: ?I intend to go with the newer solution?....and described the decision by someone else to do the same as a ?no brainer?.

rvbuilder2002 08-06-2019 08:03 PM

Quote:

Originally Posted by RV8JD (Post 1364461)
I'm glad they noted it somewhere. Now they just have to revise their published "weight-on-nose-wheel limits" Service Letter to reflect that there are no nose wheel weight limitations if the new NG mod is installed.

Already planned.... just not time to get it completed before OSH.

rvbuilder2002 08-06-2019 08:16 PM

Quote:

Originally Posted by KazooRV-9A (Post 1364528)
While the new design may perform better in a drop test, and has improved FEM results under some selected analytical load conditions, drop is only one type of load.

Clarification for those that may not be familiar with this type of testing......

The tests completed with drops are not just a simulation of what would happen if you stalled and dropped to a runway. The pitch angles that the different drops are done at are to simulated the load vector that would be applied to the nose gear in a variety of situations. There are numerous tests done for different possible scenarios.

Example - the steepest nose down attitude is applying a load that simulates the leg / wheel running into something, only done using the force of gravity in place of the force of inertia.

I think there are plans to get the test videos posted and available on line at some point.

Gabe 08-07-2019 01:42 AM

[quote=RV8JD;1364642]Here are some of your pics. I hope you weren't injured.

Hi Carl, came out of it without a scratch, surprising little damage which is a testament to the design of these aircraft.Replaced canopy,hor. stab and rudder,forward top skin,forward right side skin,shock load,new prop and hub and new nose gear leg.The other thing learned is that the canopy plexiglass is super strong and needed a few solid kicks to get out.This happened 4 years ago and 300 hours later and multiple landings on improvised strips the gear leg is holding up pretty good. I posted this to assure others with A models that in my opinion the original nose gear design does it's job well as long as one sticks to flying them as they're supposed to.

gmcjetpilot 08-08-2019 01:51 PM

Has anyone looked at the nose of a Piper Tri-pacer. it was one of the first Trikes. The wheel and tire are huge, the oleo strut is beefy and braced. A friend was in the short wing piper club told me how they tested it. back in the day. They hooked up a tractor and towed the plane 90 degrees to furrowed plowed field, quickly with heavy weights tied to the nose... You are not going to fold that up

Cessna's have strong gear but hard landings buckle the fire wall. Pacer is tube frame.


rvbuilder2002 08-08-2019 02:31 PM

Quote:

Originally Posted by gmcjetpilot (Post 1365122)
Has anyone looked at the nose of a Piper Tri-pacer. it was one of the first Trikes. The wheel and tire are huge, the oleo strut is beefy and braced. A friend was in the short wing piper club told me how they tested it. back in the day. They hooked up a tractor and towed the plane 90 degrees to furrowed plowed field, quickly with heavy weights tied to the nose... You are not going to fold that up

Cessna's have strong gear but hard landings buckle the fire wall. Pacer is tube frame.

Many of the Cessna's, Piper's, and others, are tube engine mounts/frames as well with the nose gear attached to it.
Damaged firewalls are just an additional part of the failure mode when the nose gear leg rips off of the engine mount.

rhill 08-10-2019 01:57 PM

Classic Mount & Leg resale value?
 
Classic sounds so much better then OLD mount. A returned mount & leg gets you a $700 credit,this kind of sets the price for the rest of us unfortunately.Vans list is $1200 for the mount and $267.50 for the leg. If I upgrade to the new mount $3000.00 with the reuse of some of my parts. My kits are past the return time frame. I inspected the new mount and spoke to Mitch Lock at Oshkosh and have to agree. Its a better solution. So is converting back to conventional gear. I'd need to spend $500 for an upgraded tail wheel but get rid of the problematic steps,the heavy nose gear and the new heavy cost of the upgraded nose gear parts. I'll need a lot more tail wheel time in the book and more than likely pay a higher premium till I build hours.In the end it may balance out.Anybody want to swap out?
RHill

DaveO 08-10-2019 06:25 PM

Quote:Quote:
Originally Posted by Gabe View Post
I've been following this thread with interest and would like to share my experience with my take on this. I had and still have the original nose wheel design on my 7 and experienced a nose over trying to land on an unfamiliar grass strip 1200 feet long on my last leg of phase 1 testing. My approach speed was way too high.. 80Kts.. floated and landed deep.. i should have gone round but because of the uphill landing i felt that i would make it, needless to say my nose went over the edge of the runway at approx. 5 knots and dropped about 20 feet thereby nosing over. i had the anti splat nose mod brace installed and after the event it became evident that the brace does work pretty well and that the original design is pretty strong. As others have said if one flies the nose wheel version of these amazing planes, keep the weight off the front as much as possible and fly them as it's design intends. After the repair work i went back to the said field and landed with a just under a half length remaining.

I see that you had the Antisplat on your nose wheel. I also turned mine over by landing too flat and buckled the nose gear. I believe in my case, I would have been better off not having the antisplat brace. It would have "rolled" the nose gear back against the lower cowling and thus not dug into the soil and result in flipping the plane. In my case I broke the antisplat brace. I do not have pictures on this computer to show. It is a maybe this idea would not prevented the nose over, but I could only hope. The plane was rebuilt and is flying today. Moral of the story, keep the nose wheel off the ground for as long as possible.

dwranda 08-11-2019 10:04 AM

I?m still working on the firewall forward. If there was a way to mount the new engine mount and have my cowling line up perfectly I would probably bite the bullet and spend the money for the new mount. My mount is drilled and the cowling nearly done. I?m not sure how you would line everything up and back drill the new mount in the perfect position. If someone does it please take some video and share. Vans didn?t take any video of their install.

rapid_ascent 08-11-2019 10:42 PM

I spoke to Van?s about this at OSH since I wasn?t sure how this would work either. In my case it was just curiosity since I haven?t drilled my firewall yet.

I think the way it works is there is a flat circular pad where the hole normally goes through. Normally it looks kinda like a washer has been welded on. For the predrilled firewalls the mount is supplied with a solid disk, no hole. The tube that the bolt goes through is over size so this allows some positional tolerance for the predrilled hole locations.

dwranda 08-12-2019 07:34 AM

Yeah the problem is lining up the mount and engine to the firewall so it is in perfect alignment with the already done cowling. Then back drilling through the firewall into the mount. Just from envisioning it I see how I could royally screw that up.

rvbuilder2002 08-12-2019 09:51 AM

For those that choose to do a retrofit, there is a complete set of instructions that will come with a retrofit mount/leg kit. They were developed while retrofitting the RV9A demonstrator.
Keep in mind that there is still the potential for engine alignment and spinner clearance issues.

FireMedic_2009 08-12-2019 11:05 AM

Quote:

Originally Posted by rightrudder (Post 1363043)
If it were me...

Take that $3900, purchase some extra 100LL and practice a bunch of nose-high landings at near stall speed. With proper technique, the standard nose gear will serve you just fine, and you'll have a lighter & simpler aircraft.

As for shimmy, make sure your wheels/tires are balanced, you have proper break-out force on the nose gear, and consider adding the wooden vibration dampers during the build.

I'm with you. Take the money and fly and/or use it for avionics. Unless you will be going to land at various grass fields that may not be in very good shape pocket the money. Will you get $4000 more for the plane because of the nose gear, probably not. And even if you did, didn't you pay $4000 more for the upgrade? So what did you gain? Now if you tell me I'm in the middle of the build and I can send in my unused old gear and get a credit back on it and it will only cost me $1000 or less, then ok it may be worth it. But $4000 more? Nope, not me. The old gear, oooops, "the classic gear" has served well. I'll use it for panel upgrades. If you only land on hard surface I don't see the need to upgrade the gear, even the need to use anti-splat


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