Now this may be a dumb question, but where would one find the gear boxes and such?


Thanks
tom

Cessna_pilot wrote:Now this may be a dumb question, but where would one find the gear boxes and such?


Thanks
tom

This is the big problem. If you purchase my STC, you can possibly buy new replacement parts from Cessna, which are likely to be awfully expensive.

Or you can buy the very nice, first-class 172 conversion STC kit offered by Stoots Aviation in Fairbanks, which uses all new OEM Cessna parts. Chances are his kit might be pricey because of this, but if new original mfg. parts add value for you then it may be the right choice.

Or you can scour the junkyards for a 170 that was scrapped but not because of destroyed gear boxes.

Or, you can wait a little while and see what I may be able to come up with

What... Don't you like the swept tail look Zane?

PPONK has cessna gear boxes. I have a 57 172 with parts from a 170B but the Fravel conversion is not completed. Its a basket case that I am getting tired of having sit in my shop. Guess I am getting old and inpatient.

Zane wrote:I will go on record as saying that I don't think a swept tail Cessna looks right in a tailwheel configuration. They look great as trikes, but the lines of the straight tail sitting on the ground just look... proper. As for the actual effectiveness of the rudder in straight vs swept, I'm not sure. I haven't flown a swept tail Cessna in years.

Terry wrote:

qmdv wrote:
Still would like to convert a 180B to a 182B

Tim

Haha, and then show up at a 180/185 fly-in.

Maybe even get a field approval for a swept tail on it. Really fire em up

Tim

Zane,
I have to agree. I don't particularly care for the looks of a swept tail taildragger either, and I own a swept tail albiet a trike. Personally I think the early swept tail Cessna's are the best looking trikes out there. I have never liked the look of the 'omni-vision' planes.

Bill,
I had heard that a person could swap out the tail-end for a straight tail and that was another option I had looked at.

WW

qmdv wrote:

Zane wrote:Very cool. Any conversion from tricycle to tailwheel is a worthy endeavor in my opinion.

Still would like to convert a 180B to a 182B

Tim

Let's do it, Tim!

Here's an update for those interested in the 172 conversion STC.

First, I really need to rent, borrow, beg, steal, or commandeer several 170B airframe parts to "reverse engineer". I would be happy to compensate someone for the LOAN of these parts, so I can make some measurements, and then I would return the parts. I need:

- Fwd. lower gear box bulkhead front reinforcement doublers p/n 0713495--11 and -12 (right and left)
- Inboard landing gear support bracket p/n 0713495-7 and -8 (right and left)
- Inboard landing gear attachment angle p/n 0713495-6 (only need one, identical L and R)
- Outboard landing gear support bracket p/n 0713495-3 or -4 (only need one, identical L and R)

For anyone interested in making their old 172 trainer into a great low-cost medium duty bushplane and outdoor sportsman aircraft, here's where the Fravel STC project sits now:

I'm now rewriting the STC and instruction manual so it is much less of a "major project", to streamline the installation procedure. Those who wish to source their own used parts will be able to do the conversion much faster and with far less time, effort, and carnage. Many errors, omissions, and incorrect sequences have now been corrected. It is planned to add several Cessna 175 models to this STC, since the airframes are essentially identical. This re-write project is well underway now. I expect that the new procedure and instructions will be approved before the end of the year, perhaps sooner.

Second step is to manufacture a kit of PMA approved parts to perform the tailwheel conversion. This of course requires significant time/effort/money/FAA approval. Not only will this provide a much better value (than buying new Brand C parts), it will also provide additional opportunities to streamline and simplify the installation procedure.

The long-term goal is to offer a conversion kit (and even a conversion installation service) that is priced low enough to make it very advantageous to convert your 172 rather than selling it and buying a 170.

Please contact me if you are interested in this conversion, and especially if you have the parts I need to take measurements of.

Thanks for the update!! Looks like you are moving forward!!

EZFlap wrote:.... I really need to rent, borrow, beg, steal, or commandeer several 170B airframe parts to "reverse engineer". I would be happy to compensate someone for the LOAN of these parts, so I can make some measurements, and then I would return the parts. I need:
- Fwd. lower gear box bulkhead front reinforcement doublers p/n 0713495--11 and -12 (right and left)
- Inboard landing gear support bracket p/n 0713495-7 and -8 (right and left)
- Inboard landing gear attachment angle p/n 0713495-6 (only need one, identical L and R)
- Outboard landing gear support bracket p/n 0713495-3 or -4 (only need one, identical L and R)..................

I flew a C170 for quite a few years, and will vouch for your pitch that a C172TD (just like the 170) is a great all-around medium duty bushplane.
That said, I kinda doubt you're gonna find anyone with these particular parts just laying around the hangar just waiting to be loaned out to you. I'd suggest investing a little capital & just buying them. I've never heard of this Fravel 172TW conversion, but it sounds sorta like the Lowe C150TW conversion which uses C120/140 parts (gear legs & gearbox pieces). A guy I know just did one of these conversions- he bought a derelict C140 fuselage & salvaged the parts he needed out of it, then sold off what was left to recoup some of his costs. If nothing else, aluminum prices are up now.
I think it is a great idea to include the parts needed for the conversion in a kit, as opposed to just paperwork. A lot of people would be put off by the need to scrouge up the gearboxes, etc & that would no doubt hurt sales.
Not counting any parts (which you may or may not supply), what kind of price are you considering for the STC & associated paperwork? I forget what Lowe charges but it's pretty reasonable as I recall.

hotrod150 wrote:

That said, I kinda doubt you're gonna find anyone with these particular parts just laying around the hangar just waiting to be loaned out to you. I'd suggest investing a little capital & just buying them. I've never heard of this Fravel 172TW conversion, but it sounds sorta like the Lowe C150TW conversion which uses C120/140 parts (gear legs & gearbox pieces).

Not counting any parts (which you may or may not supply), what kind of price are you considering for the STC & associated paperwork? I forget what Lowe charges but it's pretty reasonable as I recall.

I'm always amazed at what people have pack-ratted away (guilty, your honor). I know these gear box parts are in demand, however I'm sure people have them. There's no downside for someone to loan these parts to me... my offer to return the parts is now in the public domain. Can you imagine what these grass-skirted cannibals here would do to me if I didn't return borrowed parts?

As mentioned, I will offer some reasonable compensation for their help. If I invested the kind of capital that is needed to buy new Cessna parts (several thousand, over fifteen if you count new gear legs), that will only increase my cost of developing the STC, which will only add that much more to the price I have to charge. I may be the only whacko in aviation who is trying to find a way to offer a better quality product at a cheaper price. That means people should be more interested to help instead of less interested... hopefully.

The Fravel conversion is indeed based on installing 170B parts in the early 172. Most of the holes are still there to mount the additional parts, since the 172 A thru C was obviously made out of the same parts.

The Fravel STC has been offered for $500 by the Fravel family, as a "paperwork only" STC. However, that paperwork is marginal by today's standard, and requires considerable creativity and detective work on the part of the mechanic. I won't bore everyone with the details unless asked, but suffice to say that after it is rewritten it will be a WHOLE LOT easier, faster and smoother for you to do. There is a dollar value to that upgrade, although it will certainly not double the price of the STC paperwork.

In the late 70's and early 80's there was a guy in Lewiston, ID offering TD conversions on later model 152's, 172's, and he even had a 182 parked out in front. All TD's. They all had swept tails and Omnivision. His hangar always revealed the tail sections parted from the rest of the plane, undergoing structural mods.

I'm not certain whether they were STC's or 337 or whatever. He sold a number of the 152's and 172's. I'm not sure about whether he sold the one swept tail 182 I saw parked in front- I can't find any info on the existence of an STC for such an animal. In addition, anyone who has crawled in the back of an Omnivision 182 will see a large difference in the structure compared to a straight tail.

I'm just not sure how he made an Omni 182 strong enough for all the banging the tail takes, or how the current straight tail 172 conversions deal with the loads.

Anyone with insight on this?

Oh no, I may just have to buy a straight tail 172 and eventually convert...Not the L19 I want but it't a lot more economical. Ez Flap do you have a rough estimate of the cost for the parts?

King of Review Flights, No, I don't have any honest estimate yet. Anything I said now would be wild speculation.

Lesuther, I cannot speak for anyone else's conversion, but the way the loads are dealt with in the Fravel conversion is that there are two thick aluminum straps, and two shorter doubler straps, that carry the loads from the tailwheel mount plate into the fuselage structure... first through the rudderpost bulkhead and then the forward stabilizer bulkhead, plus these strap doublers tie into a foot or two worth of fuselage skin. All in all, to my feeble mind it looks like there's actually more structural tie-in on this than there is on a stock 170.

EZFlap wrote:No, I don't have any honest estimate yet. Anything I said now would be wild speculation.

Ok, I can appreciate that. I guess I will just have to follow your progress.

Sure do love my Fravel 172, I wish I had been around when it was converted, i might've been able to help with advice and suggestions.
Good to know someone is taking the reigns on this STC though.

EZFlap wrote:the way the loads are dealt with in the Fravel conversion is that there are two thick aluminum straps, and two shorter doubler straps, that carry the loads from the tailwheel mount plate into the fuselage structure...

The conversion I saw had something like this as well. Thanks.

With a whole pile of work they come out like this.............

Hey Bill....................
Why don't you send me a plane ticket and I'll just come on down there and help
you

EZFlap wrote:..... If I invested the kind of capital that is needed to buy new Cessna parts (several thousand, over fifteen if you count new gear legs), that will only increase my cost of developing the STC, which will only add that much more to the price I have to charge......

I was thinking of used parts, either bought by the piece or aquired as part of a complete fuselage as my friend did. But good luck with the borrowing, and with improving the STC.

Jimmy M wrote:
Hey Bill....................
Why don't you send me a plane ticket and I'll just come on down there and help
you

Looking at that second photo, it appears to me that you really need to go see Wup over at Bushwheels.

I'd send you a ticket to Hollywood, but you might be uncomfortably cold when you got here... this place may be a little too extreme weather for you Ontario guys. Last night the temperature in Los Angeles plunged down to +50 degrees F !