Any news on the TAF Oscar ?

[Michel Lemieux]

Just wondering

[C170BDan]

No "offical" word yet. Just know that they are working on the gear "issues" and complete the repairs.

[HarvardIV]

Not to start any speculation, but you would think that if they copied the Japanese design exactly they'd have no teething troubles wiht the gear?

[srpatterson]

Not to start any speculation, but you would think that if they copied the Japanese design exactly they'd have no teething troubles wiht the gear?

You're joking, right? We asked five different owner/pilots about the pneumatic landing gear on the Yak-11 and we got five different answers.

[HarvardIV]

No Joke, but I thought the japanese gear was always hydraulic. Did I think wrong?

[bdk]

No Joke, but I thought the japanese gear was always hydraulic. Did I think wrong?

Sometimes what is on the drawing (assuming TAF even had them) is different from what ended up in production. Especially in wartime. Things may also need to be redesigned a bit to accomodate currently available rubber seals and fittings. Reverse engineering a component also doesn't give you the information required for assembly tolerances.

[HarvardIV]

Sometimes what is on the drawing (assuming TAF even had them) is different from what ended up in production. Especially in wartime. Things may also need to be redesigned a bit to accomodate currently available rubber seals and fittings. Reverse engineering a component also doesn't give you the information required for assembly tolerances.

Ok bdk, I agree with you, as manufacturing has it's very own logic/process.

The only thing I don't agree is that reverse engineering doesn't give you tolerance info. It should, because any good copy cat will know how to use a pair of calipers.

[mrhenniger]

The only thing I don't agree is that reverse engineering doesn't give you tolerance info. It should, because any good copy cat will know how to use a pair of calipers.

You may have missed BDK's point. You might measure some dimension to be 5 mm for example. You don't know if their design was 5 mm +/- 1 mm or even 6 mm +/2 mm. Tolerances are a significant part of any design spec. I supposed you could impose your own strict tolerances, but the expense of manufacturing to those toleraces could be high.

Mike

[srpatterson]

The only thing I don't agree is that reverse engineering doesn't give you tolerance info. It should, because any good copy cat will know how to use a pair of calipers.

Assuming that the part your measuring is the correct part. We found many o-rings and gaskets in the Sea Fury that had been "slapped" together in the field, causing numerous problems. In our case we were fortunate that original documentation was available, but that isn't always the case.

[HarvardIV]

Hello Mr. Henniger:

Good points and arguments. However, I'd argue that there is a set of "default standards" which in the case of the measured dimensions could be applied. For example a set of standards for tolerances in an ASME (American Society of Mechanical Engineers) book, or in the instance that an original repair manual doesn't apply, the AC-4313 instead of the manufacturers repair manual.

Hi Mr. Patterson:

Good point, O-rings not seating, because of an overlooked impossible to see mechanical detail. Sounds like a high probability on that.

[vanguard]

You also have to remember that when you interpilate the info. That this was built in JAPAN. Even at that time in the US things wernt all standard AN. People who have worked on corsairs know about the VS system. The P-47 used totaly different O-ring dimentions. Even NORTHAMERICAN used some weird stuff in the early 40's. Read the WARBIRDS WORLDWIDE article about restoring the XP-51A for the EAA. Reverse engineering somthing isnt always as easy as it seems.

[HarvardIV]

Yes Vanguard, especially with no longer practiced methods. Ie Vought's welded sheet metal technique.

[marine air]

Who says the Japanese had it right? Maybe there are some design flaws inherent in the design. The Japanese weren't known for their engineering prowess before WWII. Many of their designs were copies and incorporations of other manufacturer's ideas. I think they bought at least one copy of every type of export fighter they could get their hands on. Maybe they made a mistake in their engineering.

[HarvardIV]

marine air:

I doubt it, because the Oscar was used all over the Pacific area, and even on rough dirt strips. If there was a problem like this, there would be a lot of people complaining about it. There would also be lots of Oscars with collapsed gear all over the place.

[marine air]

Thanks,
I know there were a lot of aircraft with major design flaws put into mass production in WW II. My primary flight instrustor, the late Col. James Haun wrote in his book "Who Says there are NO OLD Bold Pilots" wrote and used to talk about some of the dogs in the Army Air Corps. Example; The P-43 Lancer could not be three point landed it had to wheel landed, he once saw a flight of six, one by one rolled into a ball on a windy day. The Curtiss O-52 Owl had such a bad wing design that if you put it into a steep turn it would stall spin. The Curtiss AT-9 Jeep was a landing nightmare. The AT-21 was rejected by the Air Corps whom refused to accept them even for the pilotless bomb/drone program.
And then there's the Brewster Bermuda ,and others.
The U. S. had the luxury of relegating these and others to training roles or exporting under the lend lease program.
On the Oscar, if it were me I would study film if there's any available.