MXT Mods? Tires and Prop

[BradleyP]

I’m slowly concluding year 3 of MXT ownership...and still removing bugs from my teeth from my constant grins.

I’ve exhaustively searched this and other forums in search of my answer, but I could have sworn I’ve read about field approvals of the following:

1) A fixed-pitch prop upgrade that was field approved that offered comparable performance to the CS version.

2) Big tires. I want my cake and want to eat it too. I love the Nosedragger despite the constant haranguing I get from the purists, but hey, it’s mine. But really, I would like to go with 800’s or 850’s on the mains and the 700 on the nose. The good news is, I can salvage a 700 from one of my newer mains to do the trick. I hear you have to flip the four bolts on the nose to make that work.

I would like to go to the FAA with the most information possible in the hopes that our kinder/gentler FAA would allow me to make these mods to the plane. I hear if I can provide information about prior field approvals, it makes the process move much quicker.

Can anyone steer me in the right direction?

[Hale-Yes]

I have also looked for a legal way to put larger tires on my MT for many years with no luck. There are STC's available for other makes of aircraft like the Cessna 206. I have never seen a field approval for the Maule for larger tires but they are likely out there. Does anyone know of one? or two?

[Dale Smith]

I just successfully got a field approval for 26' good years on my M5.

I had 4 examples of the same thing, still had to jump through hoops with the FAA. I had to include the Data that showed the demonstrated torque in comparison to the bolts that hold the backing plate on.

Grove has a calculator on their website that goes over all that. If you want to go to the FAA without an example of previous approval that would be a good thing to include.

[Duane]

Bradley,
I have heard of people who have done that with the 7:00 on the nose. Yes, you would have to reverse the bolt direction on the torque plate. As far as approval, I don't have any ideas there.

[chris_01]

1) A fixed-pitch prop upgrade that was field approved that offered comparable performance to the CS version.

how would that work? I'd be interested, too.

[Mountain Doctor]

As someone who regrets not getting a CS instead of a FP I'm curious as to why you want to change in the opposite direction?

[Mountain Doctor]

I've seen a T series Maule with 7's in the front and 8.5's on the mains. Inverted bolts on the front. Don't know if it had paperwork, but it still seemed to fly OK. Noted at the Johnson Creek Fly In in years gone by.

[Hale-Yes]

I have heard of T models as you describe, but I have never seen one or heard of anyone talking about having a field approval for the larger tires. If anyone knows of one I would sure be interested. It's something that I would like to try. In this FAA CYA universe that we live in, compiling copies of a few field approvals seem to help our FAA friends to overcome their fear of putting their name on anything except the back of there paycheck.

[Flybrian1950]

Wup indicates it was a Maule Factory issue that prevented the "T" series planes from being included on the AML for Bushwheels, or larger 10-10 wheels.

It makes no sense, if an airglas nose fork will bolt on, that the MXT-180 could not use 8.00-6's on all three corners with the factory brakes.

A Cessna 182D with a 285hp O-520 can install the Airglas fork an 8.00-6 nose wheel and 8.00-6 Mains, using the same -97 Cleveland brakes that are approved for the plane with 6.00-6's.
If I go up to 8.50's on the mains, it looks like a brake upgrade to double pucks is required by STC
After that, I can put an 8.50-6 on the nose and 8.50-6, 26's or 29's on the mains.

If that can be done on Cessna 172's and 182's, it's hard to imagine a good reason Maule can't simply do it as an approved option for the "T" series planes on the type certificate, and let the tri-gears explore the Back Country.

[Hottshot]

Between the Factory and Airglas there wasn't enough interest in the past and when we were working on the STC for the Mains there wasn't any options for the nose. A major helping hand in the 182 STC was the ability to install a larger fork through Airglas, they do have a fork that will bolt that uses the Piper Bolt pattern Used on the Cherokee 6. The Cessna fork has a different pattern and won't fit but the STC process would be costly for so few installs so a 337 for those interested would be the only route. I sent out a couple copies of 337's I had for larger mains but don't have any with the larger fork

[Flybrian1950]

Wup, thanks for the clarification, and all your work in the past helping get bigger tires approved for all our planes.

Mountain Doctor, If you want to give the 8:00-6 on the nose and 8:00-6 on the mains a try, I will supply the Piper style airglas fork Wup says will fit.
(if you decide to keep the installation after approval, then replace the fork, if it doesn't get approved, simply return the fork).
With a copy of the field approvals from Wup on the mains and the airglas data for the 172/182/206, and the FAA bush wheel letter protocol, maybe it is possible.

With 8:00 on the mains, my thought is the stock Maule single puck brakes should be adequate, and avoids the expense of bigger brakes for this effort.

I thought I saw a drawing that 8:50-6's need double pucks for tw maules.

This airglas fork is only approved for 8:00 on the nose of the cherokee six, however the Cessna version now allows a smaller nose wheel size than the mains, so a 8:00 nose and 8:50 mains may be workable for some one with the bigger brakes on their MXT.

I'm thinking a 8:00-6 approach would make a better soft field airplane at a reasonable price. Hopefully a field approval will surface for the 7:00-6 we have all heard about.

An outfit in Idaho called Hitchcock Aviation seems to be knowledgeable on this topic in regards to the Cessna HD Gear upgrades for the 172/182/206.

[Hottshot]

Todd is the lower 48 Idaho dealer for airglas his son has taken the reins I think and will help if he can.

[DeltaRomeo]

Drawing 4146 Rev D does not mandate double puck brakes when using 8.00's or 8.50's, merely a spacer to ensure the caliper does not rub on the tire sidewall. As for 8.50's, I can lock up the tires with single puck calipers so the brakes are sufficient.

[Hottshot]

Drawing 4146 Rev D does not mandate double puck brakes when using 8.00's or 8.50's, merely a spacer to ensure the caliper does not rub on the tire sidewall. As for 8.50's, I can lock up the tires with single puck calipers so the brakes are sufficient.

Correct and honestly don't need double Puck brakes on a 850's

[Flybrian1950]

I have the new shinny Airglass Fork with axle and paperwork in hand, will need to get paperwork changed from prior owner, of this never installed fork. I believe the Maule nose wheel will work.

Just waiting for Mountain Doctor or another "young at heart, bold Pilot" to step up and get this effort underway. Brian