Kitfox S/N 1000 Restoration! N73BH

Can I test run a 912uls without a prop?!?   8 votes

  1. 1. Can I test run a 912uls without a prop?!?

    • Yes, go for it!
    • Hmm... Maybe, but be careful...
    • NO WAY!!!

Please sign in or register to vote in this poll.

36 posts in this topic

Posted (edited)

Hello! In response to YouTube comments by Jim Chuck, TJay Larsen and John Durham I am starting this thread to log the technical side of my restoration of the 1000th Kitfox EVER(!).

 

Unfortunately the right flaperon detached on take-off this May and the airplane was badly damaged, the ATP pilot did stop the engine before impact thank goodness so it appears to be OK. 

My first question is: is it OK to run the engine (Rotax 912UL with slipper clutch) without the prop to confirm that it does in fact run? OR should I wait until I can afford two new blades for the IVO prop?

Thanks,

Nile McMillion

Here's my YouTube Channel: Nile McMillion | YouTube

If you want to support what I'm doing: Help Restore Kitfox 1000!

 

Kitfox_SN_1000.thumb.jpg.521885d38f6051aJack_Fleetwood_Me.thumb.jpg.f1101c1b9c48

 

 

 

Bon Hartline's planes.bmp

Edited by flyboy01
Added poll

Share this post


Link to post
Share on other sites

Posted

Welcome Nile

looks like a great project there. How did the landing gear hold up to the accident? I see its the good Grove Gear. Have no idea about running the 912 maybe try to get a hold of Larry with the Mangy Fox he seems to know a bit about them engines and knows alot of guys running 912 engines.

Share this post


Link to post
Share on other sites

Posted

Personally I would not run the engine without a prop.  Additionally you need to do the crank test to make sure that the crank was not bent.  If the engine was not running the easy thing to do is check the runout on the prop flange.  Refer to the mantelpiece manual.  All that you will need is a dial indicator which is available from Harbor Freight.  My guess is that you will find that it is ok but if not the engine will destroy its self. Also I would pull the gearbox and do the runout on the end of the crank just to be safe.

Share this post


Link to post
Share on other sites

Posted

^ This 

After a successful run out test, you can always bolt on a test club or any old prop for an engine run. I even know someone who used a pusher prop on his tractor. Obviously, you will need to exercise caution during the run up but it will tell you whether the engine is in good running condition or not and prevent an inadvertent engine damaging overspeed event.

Share this post


Link to post
Share on other sites

Posted

Welcome Nile

looks like a great project there. How did the landing gear hold up to the accident? I see its the good Grove Gear. Have no idea about running the 912 maybe try to get a hold of Larry with the Mangy Fox he seems to know a bit about them engines and knows alot of guys running 912 engines.

The landing gear held up admirably, they did bend in a little on the left side though. Any suggestions on straightening those?

Personally I would not run the engine without a prop.  Additionally you need to do the crank test to make sure that the crank was not bent.  If the engine was not running the easy thing to do is check the runout on the prop flange.  Refer to the mantelpiece manual.  All that you will need is a dial indicator which is available from Harbor Freight.  My guess is that you will find that it is ok but if not the engine will destroy its self. Also I would pull the gearbox and do the runout on the end of the crank just to be safe.

Thanks for the advice I will definitely try measuring the runout.

^ This 

After a successful run out test, you can always bolt on a test club or any old prop for an engine run. I even know someone who used a pusher prop on his tractor. Obviously, you will need to exercise caution during the run up but it will tell you whether the engine is in good running condition or not and prevent an inadvertent engine damaging overspeed event.

The IVO prop didn't break off, only cracked two of the blades and pushed them in a bit, could I run that? Also, What's a test club?

 

Share this post


Link to post
Share on other sites

Posted (edited)

I would not run a damaged prop. Test clubs are short blade wood props made to provide load, inertia and cooling on an engine during a test run or break-in procedure.

[edit] I remember reading the article above on this plane, have it somewhere. Neat 'provenance', glad to se repair underway.

Edited by dholly

Share this post


Link to post
Share on other sites

Posted (edited)

Definatly don't run the blades you have.  You can't imagine how much that engine will shake if the prop is out of balance.  I hit some slush on a frozen lake one time, and it flew up into the  wood prop. A piece of the trailing edge that was maybe at the most 1/2" wide by a foot or so long and pretty thin broke off.  At a medium idle, it felt like the engine was going to shake off the front of the plane.   It's tempting to want to hear the engine run, but remember, it was running fine before the crash, and should run fine now if it wasn't damaged.  Worry about the rest of the plane for now is my advice.  Here are a couple of pictures of two different  ways to do your rib tail repair that I couldn't post on the Team Kitfox site.  If you do this repair, use the right kind of plywood.  This was for an Avid Flyer, but the Kitfox is very similar. JImChuk

Photo0653.jpg

Photo0655.jpg

Edited by 1avidflyer

Share this post


Link to post
Share on other sites

Posted (edited)

 

 

Unfortunately the right flaperon detached on take-off this May and the airplane was badly damaged

 

 

Why did the flaperon detach? That could be an useful information for other pilots!

Edited by Jeromef

Share this post


Link to post
Share on other sites

Posted

Only thing doing a runout test on the flange tells you if the flange is bent. Its the gear train that gets damaged usually on the rear of the engine with the drive systems. With a gearbox, damage to the engine is usually nil. Just a minor prop strike normally just damages the prop. A sudden stoppage can do major damage to the other parts of the drive train which can run normally for a while up to failure.  Any sudden stoppage SHOULD require a teardown at the least. That's why one should use caution when buying a used 912.  An engine turning 4-5000 rpm's gets stopped suddenly, its not rocket science as to what keyway's get sheared or gear bolts get overstressed including the accessories that are bolted to the rearend.  Bad thing is, teardowns are not cheap and are usually put off till its too late or the engine is passed on to the next buyer.

Share this post


Link to post
Share on other sites

Posted

I talked to Hal from Zipper Big Bore this morning and he (along with my motorcycle mechanic/Machinist dad) said he runs the 912 without a prop all the time with no damage.  We checked the prop flange for run-out and it was .00005" or half a thousandth out of wobble which is almost nothing. 

 

 

Unfortunately the right flaperon detached on take-off this May and the airplane was badly damaged

 

 

Why did the flaperon detach? That could be an useful information for other pilots!

I'm still investigating but I know there was a Mandatory Service Bulletin on it in the UK. They appear to have de-laminated and then failed, as far as I know this is only one of three times this has happened. The service Bulletin calls for reinforcing the rib tails with aluminum angle. Here's the NTSB report https://app.ntsb.gov/pdfgenerator/ReportGeneratorFile.ashx?EventID=20180503X02040&AKey=1&RType=Prelim&IType=LA

Share this post


Link to post
Share on other sites

Posted

Only thing doing a runout test on the flange tells you if the flange is bent. Its the gear train that gets damaged usually on the rear of the engine with the drive systems. With a gearbox, damage to the engine is usually nil. Just a minor prop strike normally just damages the prop. A sudden stoppage can do major damage to the other parts of the drive train which can run normally for a while up to failure.  Any sudden stoppage SHOULD require a teardown at the least. That's why one should use caution when buying a used 912.  An engine turning 4-5000 rpm's gets stopped suddenly, its not rocket science as to what keyway's get sheared or gear bolts get overstressed including the accessories that are bolted to the rearend.  Bad thing is, teardowns are not cheap and are usually put off till its too late or the engine is passed on to the next buyer.

Thankfully, The owner/passenger killed the engine before impact so I would be surprised if the engine or crank was damaged, nonetheless I'm still going to check the crank with a dial indicator. 

Share this post


Link to post
Share on other sites

Posted (edited)

Definatly don't run the blades you have.  You can't imagine how much that engine will shake if the prop is out of balance.  I hit some slush on a frozen lake one time, and it flew up into the  wood prop. A piece of the trailing edge that was maybe at the most 1/2" wide by a foot or so long and pretty thin broke off.  At a medium idle, it felt like the engine was going to shake off the front of the plane.   It's tempting to want to hear the engine run, but remember, it was running fine before the crash, and should run fine now if it wasn't damaged.  Worry about the rest of the plane for now is my advice.  Here are a couple of pictures of two different  ways to do your rib tail repair that I couldn't post on the Team Kitfox site.  If you do this repair, use the right kind of plywood.  This was for an Avid Flyer, but the Kitfox is very similar. JImChuk

Photo0653.jpg

Photo0655.jpg

Thanks Jim for the pics and advice, I just took the prop off and there is nooo way i'm even thinking of trying it anymore! :o 

Edited by flyboy01

Share this post


Link to post
Share on other sites

Posted

I just uploaded a new video that overviews what has to be done and the fiberglass work on the cowling, I did forget to mention that I do need to straighten the upper portion of the cockpit where the wings attach and replace tubing on the door trusses which straightened in about a hour with a C-clamp and some square tubing.  I plan to do a video dedicated to straightening and replacing tubing since the only other one I could find was from the 1940's.(!)

Sorry about the intro and outro quality...

Share this post


Link to post
Share on other sites

Posted

Hello everyone! I'm back from vacation and ready to hit it! I bought some bar clamps to help straighten the tubing, a new soldering iron for doing fine work on the instrument panel and other avionics, my dad gave me some sweet brand new off-road LED lights that I'll mount on the end of main struts for landing lights (reeaallly bright!) I've got tubing in my cart at aircraft spruce and it turns out my local hardware store has the best prices on windshield grade plexiglass anywhere! My next video should be published soon so if want to support what I'm doing Click Here! I really want to upload pictures but the forums haven't been working for me the last couple of days.

Signing off for now!

Nile

Share this post


Link to post
Share on other sites

Posted

Get with it then!  :-)  I did notice you said plexiglass when you mentioned windshield.  Unless you intend to heat form it, you will have problems bending plexiglass.  Maybe you meant Lexan, actually that's a brand name, the type name is polycarbonate.  That will bend and not crack.  I would be very afraid of plexiglass in the windshield.   Just a couple of days ago, I picked up two sheets of .060" X 4 X 8  polycarbonate from Seeley Plastics for $48.50 each  JImChuk

1 person likes this

Share this post


Link to post
Share on other sites

Posted

Thanks Jim, i. I did mean Plexiglass, as in Acrylic. the stuff I would be using would be .100 acrylic sheet with a 10 year no-craze or yellow warranty: https://plaskolite.com/catalog/optix-acrylic/ I would heat form it like these guys did on a Kitfox: Kitfox windshield How to replace It Simple I live 2.5 hours from the nearest big town and 45 minutes from a very small town so I don't exactly have easy access to most supplies.

Share this post


Link to post
Share on other sites

Posted

In the video you linked to, Dave was using Lexan.  (polycarbonate)  JImChuk

Share this post


Link to post
Share on other sites

Posted

Thanks for the correction Jim, I will look into polycarbonate.

Share this post


Link to post
Share on other sites

Posted

It's been a long time since I've posted anything on here, but thanks to the amazing amount of support I've been blessed with from my GoFundMe campaign, I am happy to say that I will be ordering the 4130 Tubing I need from A.S. this week. I would love to get your opinions on anything you would do differently or anything else I should order. Thanks for your support!

Share this post


Link to post
Share on other sites

Posted

Alright! Tubing is on its way! BTW has anyone ever tried straightening Grove Gear? The pilot's side is bent in about ~4-5 inches. What are your opinions on Grive vs Cabane vs Standard? Does anyone have a set of gear they would be willing to part with for cheap? 

Share this post


Link to post
Share on other sites

Posted

Grove can straighten the gear.  Not for free of course....  Maybe if a guy had access to the right press, he could do it himself.   I was just straightening out some tail springs yesterday on my 20 ton Harbor Freight press.  It worked.  JImChuk

1 person likes this

Share this post


Link to post
Share on other sites

Posted

The earlier Grove gear can sometimes be straightened but they have been using 2024 for quite a while now and they will not straighten those.  Best bet is to give them a call with the serial number and they will tell if it is possible. 

Share this post


Link to post
Share on other sites

Posted

Did you mean 7075-T6 ? I don't know how long my grove gear have been on but I suspect they were installed in 2008.  I'll give them a call but I am also open to building or buying other gear.

Share this post


Link to post
Share on other sites

Posted

Yes you are correct at any rate check with them ,some can be straighten and some can not.

Share this post


Link to post
Share on other sites

Posted

So grove just responded to this e-mail I sent:

Hello, I have a model III Kitfox with Grove Gear that was involved in a accident. The pilot’s side has been bent in about 2 inches. The serial number is HH604-75, is it possible straighten these gear or will I have to replace them.

Thank you,

Nile McMillion

And I got this response:

Hi Nile,

Unfortunately, your gear was manufactured by Hammer Head and not Grove. As it is no longer cost effective for us to repair that manufacturers gear, we recommend you order a new one.

Thank you,

Florence Baldino

Grove Aircraft Landing Gear Systems Inc.

Does anyone know anything about this? I can't find anything online except for a Hammer Head Aviation that only makes composite parts like cowlings and wheel pants. Also what Oil Cooler are you running on your 912? Mine is a Earl's Performance Products oil cooler but it needs to be replaced. Any help is appreciated! 

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now