gross weight increase for 170

[4stripes]

Is there any STC that allows a gross weight increase for our 170's? There's one listed on ebay that indicates this (2550lbs)! It also has a square tail (aka early 172). Is there an STC for this square tail mod (not that I would change mine)?
Cheers Eric

[Bruce Fenstermacher]

To the best of my knowledge there is no STC to increase the weight limit of the 170 available for any configuration. If there was I would think we (the associationforum collective) would know about it and many more would have it.

If course I didn't know there was an STC to install a 175 tail either and I'm not surprised if such an STC exists that we (the associationforum collective) don't care much about it.

I've never heard of a 12 volt 25 amp 28 volt 60 amp alternator either. I wouldn't be surprised if the seller doesn't know what he's selling. I know you didn't ask this but if I was buying that plane I'd be looking at the paperwork REAL CLOSE.

[GAHorn]

The aircraft listed is a highly modified airplane owned by a "MASTER MECHANIC" A&E-IA/DAR/DME/ "MASTER PILOT"/CFI-GI/ATR/LTAP/MPR/ CTO (these are all his words from his resume'). He has sliced/diced/peeled/julienned/chopped/modified that airplane in more ways than Ron Propeil and, because he is a "designee".... he has approved much of his own work. He is now offering it for sale. It's up for debate as to whether the modified result is a 170 or not and whether it's airworthy or not. There is no STC for increased gross wt. for a 170 that I am aware of other than the one he claims to have for that particular heavily-modified airplane. The question I'd ask of any claimed gross wt increases is: What's the useful load? (Gross wt increases aren't of much value when you're just trying to make up for the fat empty wt created due to silly mods like dual batteries for 28-volt conversion, etc..)
(In an unrelated event, the owner/seller is the same guy who ran out of oomph and landed on a Calif. highway, got out leaving it running, then when a passing motorist honked and waved at him, he absent-mindedly waved back... and lost part of his hand in the whirling propeller. He got a ride to the hospital instead of a ride in his flying machine.)

[squaretail]

WoW! Is part about the hand in the prop for real.

[lowNslow]

The aircraft listed is a highly modified airplane owned by a "MASTER MECHANIC" A&E-IA/DAR/DME/ "MASTER PILOT"/CFI-GI/ATR/LTAP/MPR/ CTO (these are all his words from his resume'). He has sliced/diced/peeled/julienned/chopped/modified that airplane in more ways than Ron Propeil and, because he is a "designee".... he has approved much of his own work. He is now offering it for sale. It's up for debate as to whether the modified result is a 170 or not and whether it's airworthy or not. There is no STC for increased gross wt. for a 170 that I am aware of other than the one he claims to have for that particular heavily-modified airplane. The question I'd ask of any claimed gross wt increases is: What's the useful load? (Gross wt increases aren't of much value when you're just trying to make up for the fat empty wt created due to silly mods like dual batteries for 28-volt conversion, etc..)
(In an unrelated event, the owner/seller is the same guy who ran out of oomph and landed on a Calif. highway, got out leaving it running, then when a passing motorist honked and waved at him, he absent-mindedly waved back... and lost part of his hand in the whirling propeller. He got a ride to the hospital instead of a ride in his flying machine.)

He even has landing lights in both wings, who in there right mind would put in a mod like tha.......oh yeah.

[Bruce Fenstermacher]

He even has landing lights in both wings, who in there right mind would put in a mod like tha.......oh yeah.

Karl, I took note of that as well. It's a slippery slope. Starts with the innocent extra landing light then a baggage door. Next will be a square tail and before you know it you have to change your signature to: "Mostly original for some reason. "

[GAHorn]

WoW! Is part about the hand in the prop for real.

Here's one version printed by the NY Times:
http://query.nytimes.com/gst/fullpage.h ... A965958260

(I'm saving a finger for Karl and Bruce.)

[squaretail]

Yeehoo! I know it is serious,but a fellow pilot crash landed to help find the finger of the guy who pushed an airplane with the engine running. Sounds like a Laurel and Hardy scene.

[blueldr]

THE SQUARE TAIL ON HIS AIRPLQANE IS A GRAFTED ON TAIL FROM A C-175. THE ENGINE IS A LYCOMING O-360.

[4583C]

He even has landing lights in both wings, who in there right mind would put in a mod like tha.......oh yeah.

Karl, I took note of that as well. It's a slippery slope. Starts with the innocent extra landing light then a baggage door. Next will be a square tail and before you know it you have to change your signature to: "Mostly original for some reason. "

Now Bruce you know George loves those round tails... I'm thinking maybe an alternator to keep up with those extra lights or maybe some Benham or Bartone exhaust stacks to keep those unsightly stains off the cowl!

[GAHorn]

I won't mention the family member who suggests "An unreasonable, original nut." , to which another suggested "an aboriginal nut".

[Chris Christensen]

During one of my visits to 'listen' to Harry Delicker, I happened to make the mistake of asking if he had ever tried to get an STC for a weight increase in the 170s.

The conclusion, after some hours of frustration induced rantings from Harry, I learned, was that the FAA would not authorize a weight increase until, and after, the 172s came out with a "STEPPED" firewall. That is where there is a small 'shelf' on the top end of the later 172 firewalls. So I was EMPHATICALLY informed.

Harry never could get them to explain why the 170 and early 172s could not carry the same weight.

Maybe George can figure it out, if not, Blueldr might have an idea or two left over to trump him with.

[GAHorn]

There are many requirements that must be met in order to justify a gross wt. increase for an existing design. More horsepower alone isn't one of them.

Certification requires a demonstration (or engineering documentation) of the structural integrity not being compromised, not only for level flight, but for gust-loads and for landing stresses, etc.... but ... here's an oft overlooked one.... balked-landing climb requirement. Just because an airplane is strong enough, doesn't make it capable of making a last minute rejected landing and meet climb requirements. Horsepower can help... but the heavier engine then steals airframe strength-reserves....so the airplane may no longer meet necessary strength and performance reserves.

Cessna ran into this in 1981 when they increased the gross wt of the 172-P model to 2400 lbs. How did they do it? They reduced the maximum flap setting from 40 to only 30-degrees to improve the balked-landing climb requirement and also relieve the stress-loads on the rear wing attach points from the additional weight, so they could handle the increased weight. Of course, that hurt landing distance numbers and it lowered the service ceiling, but ...everything in aviation is a compromise.

The point is... it's not as simple as it sometimes seems it should be.

[jatkins]

THE X WING COMPANY has a gross weight increase for the Cessna 170/B

http://www.wingxstol.com/main-en.html

The weight increase requires 180HP or more , and the wing Mod.
The 180HP probably takes care of the balked landing requirements ?

http://www.wingxstol.com/images/graphs/1.gif

[4stripes]

This increase is up to 2400lbs, not the 2550 claimed in the ad.
Thanks Eric