STC for 850s?

[Zmonroe10]

So I was able to find one thread on this topic but was wondering what the general consensus on it would be. I recently purchased a 1941 DC-65. It has the standard 6.00-6 shinn wheels and tires. With those and the solid tailwheel, any grass strip that isn’t well rolled feels pretty rough.

So I beg the question, do I need an STC or field approval to put 8.00 or 8.50 tires on my shinn wheels? The TCDS A-746, under landing gear section, states “103. 6.00-6 wheels (Shinn 6C4) with 6.00-6 2-ply tires 22 lb. (+0)”. However, it also says a few lines down “304. 6.00-6 wheels (Shinn 6C4HB) with brakes +6 lb. (0)”.

Does line 304 cover me to put any tire size on 6.00-6 wheel? Or, would I need to go through the process of making it legal some other way? Any input is appreciated!

[N96337]

I always got a field approval... but I guess in some FSDO's that's improbable to impossible anymore?
John

[Mike S]

I plan on installing 8.50s on mine as well. My IA said it could be done via field approval when the time comes and over in the Tech Resources section there are example 337s for 8.50-6 installs.

[astjp2]

I have them on mine, some interpretations of the cars say it’s a log book entry. One of those 337’s is mine. What brakes do you have?

[1938BF50]

Mine was a field approval/337 with the Milwaukee FSDO. All that he wanted to verify was that no interference of brakes or gear existed with the bigger tires.

[N96337]

some interpretations of the cars say it’s a log book entry.

I agree....but the "modern fed".....

[astjp2]

I agree....because the "modern fed knows nothing about 80 year old fabric covered non-electrical system airplanes".....

Fixed it for you...

[N96337]

Exactly!!! Although my PMI at least has a sense of humor about it. When we were working on some additional fabric procedure approvals, he looked at me and said I was the one he always calls for fabric answers, so now what's he gonna do about this one?

[Zmonroe10]

I have them on mine, some interpretations of the cars say it’s a log book entry. One of those 337’s is mine. What brakes do you have?

I've just got the factory Shinn expansion brakes but the work very well, better than many modern hydraulic brakes.

[astjp2]

Well I can let you try my single puck hydraulic brakes. when you can stop in 250 feet and be able to taxi by using the brakes and a high power setting and keep the tail off the ground, let me know. The shin’s were marginally better than the oak skid on the tail for stopping. Tim

[Hank Jarrett]

If your shin’s were marginally better than the oak skid, your skid must have been polished smooth! ;-)