I put the 175 wings on my 170B and thought it was great. There maybe some unusual situation where you may not get all the fuel out, I don't know, but for 99.9% of "normal' flying, most of the fuel in the tank was usable. I thought it was an easy/affordable way to increase fuel capacity y 10 gal+_. I'd do it again.

shortfielder wrote:I put the 175 wings on my 170B and thought it was great. There maybe some unusual situation where you may not get all the fuel out, I don't know, but for 99.9% of "normal' flying, most of the fuel in the tank was usable. I thought it was an easy/affordable way to increase fuel capacity y 10 gal+_. I'd do it again.

Did you modify the tanks with fore and aft pickups? I don't doubt you could get most of the gas out of these tanks, just wondering if you can get around the legality of 9 gallons unuseable fuel.

MTV

MTV on the 175/172 LR tanks with the standard single point pickup you are not packing unusable fuel. In normal flight. When you run one of those tanks dry they are DRY. There is nothing left in those tanks, Zero.
The paperwork say 52 gallons capacity , 48 gallons usable. Believe me you can use every drop of that 52 gallons in normal flight.

MTV on the 175/172 LR tanks with the standard single point pickup you are not packing unusable fuel. In normal flight. When you run one of those tanks dry they are DRY. There is nothing left in those tanks, Zero.
The paperwork say 52 gallons capacity , 48 gallons usable. Believe me you can use every drop of that 52 gallons in normal flight.

+1

175 magnum wrote:MTV on the 175/172 LR tanks with the standard single point pickup you are not packing unusable fuel. In normal flight. When you run one of those tanks dry they are DRY. There is nothing left in those tanks, Zero.
The paperwork say 52 gallons capacity , 48 gallons usable. Believe me you can use every drop of that 52 gallons in normal flight.

I totally understand that. But flying airplanes actually USUALLY requires some change in pitch attitude.

Further, my airplane is tailwheel converted. Even if I maintained a level attitude to the touch, it’s gonna be hard to splain to the nice FAA guy why the engine quit in the middle of the runway when the tail came down.

The term “unuseable fuel” is that fuel which is not available in ALL normal flight attitudes.....NOT that fuel which is unavailable in level flight. That is a certification requirement. Please re-read that......

I have experienced engine failures in flight.....not because I ran out of gas, though.....I swore a long time ago I’d never do that.

So far, so good.

MTV

Looking for info.. is there an stc for 172 wings for a 170b... I realize there is a stc for the 175 wing... are the 172 and 175 the same wing . thks in advance..

shadow585 wrote:Looking for info.. is there an stc for 172 wings for a 170b... I realize there is a stc for the 175 wing... are the 172 and 175 the same wing . thks in advance..

No STC exists for 172 or 175 wing on 170. Field approval required.

There is a one time STC for swapping 175 wings on a 170B by Stene but it was for a specific serial number.

mtv wrote:

shortfielder wrote:I put the 175 wings on my 170B and thought it was great. There maybe some unusual situation where you may not get all the fuel out, I don't know, but for 99.9% of "normal' flying, most of the fuel in the tank was usable. I thought it was an easy/affordable way to increase fuel capacity y 10 gal+_. I'd do it again.

Did you modify the tanks with fore and aft pickups? I don't doubt you could get most of the gas out of these tanks, just wondering if you can get around the legality of 9 gallons unuseable fuel.

MTV

I’m still curious how you mated the single outlet 175 tank to the two pickup fuel system in the 170.

MTV

175 magnum wrote:MTV on the 175/172 LR tanks with the standard single point pickup you are not packing unusable fuel. In normal flight. When you run one of those tanks dry they are DRY. There is nothing left in those tanks, Zero.
The paperwork say 52 gallons capacity , 48 gallons usable. Believe me you can use every drop of that 52 gallons in normal flight.

The flight manual for my 1958 175 clearly states that the tanks hold 52 gallons, and that only 43 gallons are useable. That means you cannot use that nine gallons, even as a required reserve, LEGALLY.

Now, how YOU use that fuel is up to you.

MTV

Stock 170A and 170B have single fuel pickup just aft of the in wing root fuel gauge. The line runs aft and down the aft door post.

Tim

bat443 wrote:Stock 170A and 170B have single fuel pickup just aft of the in wing root fuel gauge. The line runs aft and down the aft door post.

Tim

Interesting, I THOUGHT my old 170B had a fore and aft pickup....but maybe not. Been a while since I opened up a wing root on it.

MTV