Air plains GWT increase STC question

Does your 172 already have a 180 HP O-360 on it? If so, what STC was used? And was any max gross weight increase part of that STC? Are your flaps currently limited to 30 degrees, or do you have an older 172 with flaps that extend 40 degrees? Knowing the answers to those questions will help provide a better answer.
 
Give them a call to find out. They're probably at Oshkosh this week and will be back next week. They're some good guys out there, and will be glad to answer your questions.
 
Does your 172 already have a 180 HP O-360 on it? If so, what STC was used? And was any max gross weight increase part of that STC? Are your flaps currently limited to 30 degrees, or do you have an older 172 with flaps that extend 40 degrees? Knowing the answers to those questions will help provide a better answer.

It won't have any of the STC's modifications until after the STC is installed.
 
It won't have any of the STC's modifications until after the STC is installed.
I think you missed my point. If David already had an STC'd installation of a 180HP engine that did not include the gross weight upgrade (and that is a possibility), he'd need another STC'd alteration to up the max gross. The way he wrote the post suggests that might be the case, and he's concered he'd need to replace his existing 180HP engine with an Air Plains-provided 180HP engine before getting the GW upgrade.
 
I think his plane has the O-320...
If that's true, then he's going to have to upgrade the engine in order to get the 200 lb MGW increase. Dunno if Air Plains only sells the STC if you get an engine from them, but I know Penn Yann will sell you their 180HP/MGW increase STC and let you find your own engine. Different prop required for all of them, too, but I'm not sure about the engine mount. Of course, you don't have to buy a new engine -- rebuilt, overhauled, or even serviceable will do just fine. However, I think Penn Yann and Air Plains will take your old O-320 in trade on an overhauled O-360 if you buy their STC.

BTW, the STC does specify the specific sort(s) of O-360 you have to use -- I think the Penn Yann specifies an O-360-A4M. Dunno if other submodels of O-360 are acceptable -- see the STC or contact the STC holder for details.
 
I think you missed my point. If David already had an STC'd installation of a 180HP engine that did not include the gross weight upgrade (and that is a possibility), he'd need another STC'd alteration to up the max gross. The way he wrote the post suggests that might be the case, and he's concerned he'd need to replace his existing 180HP engine with an Air Plains-provided 180HP engine before getting the GW upgrade.

I believe we read the question differently, he is asking if he must use the air-plaines engine, the answer is no, the STC will dictate make and model not who sells the engine.
 
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If that's true, then he's going to have to upgrade the engine in order to get the 200 lb MGW increase. Dunno if Air Plains only sells the STC if you get an engine from them, but I know Penn Yann will sell you their 180HP/MGW increase STC and let you find your own engine. Different prop required for all of them, too, but I'm not sure about the engine mount. Of course, you don't have to buy a new engine -- rebuilt, overhauled, or even serviceable will do just fine. However, I think Penn Yann and Air Plains will take your old O-320 in trade on an overhauled O-360 if you buy their STC.

BTW, the STC does specify the specific sort(s) of O-360 you have to use -- I think the Penn Yann specifies an O-360-A4M. Dunno if other submodels of O-360 are acceptable -- see the STC or contact the STC holder for details.

The web page gives us this
http://www.airplains.com/index.php/parts/engine-conversion/80

and does not require he buy their engine.

it's irrelevant if he already has the STC installed, the O-360-A2F,A3A, A4A, A4M, A4N are used depending upon which model 172 he has.

http://www.airplains.com/index.php/parts/engine-conversion/80

That's what is included in the STC kit, I see no engine listed. Plus I doubt they will sell you a used engine as "serviceable" seeing as they rebuild them.
 
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They will do it both ways

http://www.airplains.com/index.php/parts/engine-conversion/80

Installation
Air Plains Skyhawk conversion replaces your old Continental O-300 engine with a factory new Lycoming O-360 180 Horsepower engine.
We are often asked what makes the Air Plains 180 different from our competition. Our complete kit concept, design for long term durability, and personal service set us apart. The installation takes an average of 60 man hours to complete. Turn around time can be 5 full days, with sufficient scheduling if you decide to have Air Plains install your new engine. Should you choose our ship-out kit, the average installation times at shops around the country range between 70 to 80 man hours for the first time installer.

1. Complete 180 HP Conversion - New Firewall Forward, propeller and Factory New engine O-360-A4M are included
2. Air Plains Kit Only - All hardware and propeller included. Engine is purchased separately.

Whether installed here at our facility or shipped to your local shop for installation, your Air Plains 180 Horsepower engine conversion will be delivered as an all-encompassing kit. Installation instructions, blueprints, and continued airworthiness manual safeguard the procedures and standards for installation and maintenance of your new conversion...no matter where you choose to have your conversion installed.
 
I believe we read the question differently, he is asking if he must use the air-plaines engine, the answer is no, the STC will dictate make and model not who sells the engine.
Well, I think that may be what he's asking, but I'd like to know for sure.
 
I've got an O-360A4M with the STC done by bush conversions with 40 degrees of flaps. Currently my gross weight is 2300
 
I've got an O-360A4M with the STC done by bush conversions with 40 degrees of flaps. Currently my gross weight is 2300

Then I'd say leave it alone and don't bother with the STC. The 40-degree flaps are nice.
 
I've got an O-360A4M with the STC done by bush conversions with 40 degrees of flaps. Currently my gross weight is 2300

Then I'd say leave it alone and don't bother with the STC. The 40-degree flaps are nice.

30 degree flaps with the Penn Yan 180 hp conversion on the club's C-172N resulted in an additional 250 pounds max gross. That gives the 172 over 100 pounds more cabin load than our 182P when then tanks are full (50 gal for the 172, 74 gal for the 182). Limiting the flaps does have its advantages.
 
30 degree flaps with the Penn Yan 180 hp conversion on the club's C-172N resulted in an additional 250 pounds max gross. That gives the 172 over 100 pounds more cabin load than our 182P when then tanks are full (50 gal for the 172, 74 gal for the 182). Limiting the flaps does have its advantages.

I've always found the 40 degree flaps more useful than the extra 250 pounds

You can get in shorter, and with the 180 horses you can get out of the same field.

The 250 pounds is for fat guys and long runways. :)
 
You know David - I'm with Tom on this one. I like my 40 degrees of flaps, too... and 'sides, you don't really need to be tempted to carry that extra weight.

Ryan
 
Yeah, sounds like the 180 with 40 degrees of flaps is an uncommon thing, and I like being different.

Thanks for the input guys.
 
Yeah, sounds like the 180 with 40 degrees of flaps is an uncommon thing, and I like being different.

Thanks for the input guys.
Then do the XP mod.. 220 horse IO-360KB
 
Call Penn Yann -- if you have the 180HP engine installed already, I think they will sell you an STC to just modify the flap switch to limit flaps to 30 degrees and get a 2550 MGW. Dunno if Air Plains does that or not. Unless you're going into really short, obstructed strips, I think you'll find the extra useful load more valuable than the extra 10 degrees of flap, but YMMV.
 
I've always found the 40 degree flaps more useful than the extra 250 pounds

You can get in shorter, and with the 180 horses you can get out of the same field.

The 250 pounds is for fat guys and long runways. :)

Hey! I'm not fat. Overweight, yes. Fat, no. And given that the majority of my trips are with just two aboard, cabin load really isn't critical.
 
Ron- Airplains will sell the STC paperwork separately as well, but you do need to have the correct prop engine combination. On the K there is a airframe mod that needs to be done as well as the Flap range fix to get to the higher load limit.
I opted for the 40 degrees and no changes for weight but that suits my (and my Wife's) mission.
Climbs well with the standard prop pitch.
Patrick
 
Their website says: "Flaps are limited to 30º to comply with minimum climb-rate requirements at full gross-weight."
Maybe this is a dumb question, but why can't there just be a limitation that flaps are limited to 30 degrees at the new weight but if loaded at the old weight (or less) the full 40 can be used? Seems like that's the best of both worlds, right?
 
Their website says: "Flaps are limited to 30º to comply with minimum climb-rate requirements at full gross-weight."
Maybe this is a dumb question, but why can't there just be a limitation that flaps are limited to 30 degrees at the new weight but if loaded at the old weight (or less) the full 40 can be used? Seems like that's the best of both worlds, right?

The real question is, with 180 horse power and that increased climb rate, who will limit the 250 added weight?
 
I sent them an email, the STC only works with one of their emails. The price for an extra 200 pounds? $40,000.

So, per extra pound it would cost me $200. No thanks
 
Their website says: "Flaps are limited to 30º to comply with minimum climb-rate requirements at full gross-weight."
Maybe this is a dumb question, but why can't there just be a limitation that flaps are limited to 30 degrees at the new weight but if loaded at the old weight (or less) the full 40 can be used? Seems like that's the best of both worlds, right?
That would be nice, but the FAA doesn't trust us that far. :sigh:
 
I sent them an email, the STC only works with one of their emails [did you mean to say "STC"?]. The price for an extra 200 pounds? $40,000.

So, per extra pound it would cost me $200. No thanks
Was that Air Plains or Penn Yann who said that? And did you try the other?
 
Their website says: "Flaps are limited to 30º to comply with minimum climb-rate requirements at full gross-weight."
Maybe this is a dumb question, but why can't there just be a limitation that flaps are limited to 30 degrees at the new weight but if loaded at the old weight (or less) the full 40 can be used? Seems like that's the best of both worlds, right?

Having flown C-172Ns with both 30 and 40 degree flaps I can tell you that you have to consiously limit the 40 degree flap machine to 30 degrees. Typically when I want full flaps I just put the lever all the way down without even looking at it. Wouldn't be safe if loaded to the higher gross.

Oh, and a 180 hp C-172N doesn't really climb well with 30 degrees hanging out in the breeze. Well, actually, it climbs reasonably well, but the ASI is way below where you expect it to be at full throttle. Or so a little birdy tells me. :redface:
 
Oh, and a 180 hp C-172N doesn't really climb well with 30 degrees hanging out in the breeze.
Right -- probably just about as poorly as a 160HP C-172N with either 30 flaps and 150 lb less weight or 40 flaps and 250 lb less weight. IOW, they all just barely meet the "balked landing" requirement of 23.77(a) for a 3.3% climb gradient at sea level with landing flaps (the 172 being unable to retract the flaps "in two seconds or less without loss of altitude and without sudden changes of angle of attack").
 
Having flown C-172Ns with both 30 and 40 degree flaps I can tell you that you have to consiously limit the 40 degree flap machine to 30 degrees. Typically when I want full flaps I just put the lever all the way down without even looking at it. Wouldn't be safe if loaded to the higher gross.

Some cessna have a flap selector that has intemediate stops and won't move beyond certain settings unless you push the lever to the right before trying to move it down further. I don't recall if the ones I flews with 40 degree flaps had that. I suspect not. But I would think adding something something like that with a stop at 30 degrees should solve your concern.

That would be nice, but the FAA doesn't trust us that far. :sigh:

It's unfortunate that those that would follow the rules are punished because of those that won't. But I've seen enough casual attitudes towards weight and balance to think it's not an unjustified position for the FAA to take.
 
Some cessna have a flap selector that has intemediate stops and won't move beyond certain settings unless you push the lever to the right before trying to move it down further. I don't recall if the ones I flews with 40 degree flaps had that. I suspect not.
IIRC, the detents were only at 10 and 20 -- and maybe not even at 20.
But I would think adding something something like that with a stop at 30 degrees should solve your concern.
No doubt, but the FAA would probably consider this an unauthorized alteration of a control.
It's unfortunate that those that would follow the rules are punished because of those that won't.
And this makes aviation different from the rest of life how?:D
But I've seen enough casual attitudes towards weight and balance to think it's not an unjustified position for the FAA to take.
Since God often punishes failure to stay within weight and cg limits more severely than the FAA is authorized to do, I'd think fear of dying would be more effective than fear of FAA retribution, but again, unfortunately, the record suggest that it doesn't.:nonod:
 
Since God often punishes failure to stay within weight and cg limits more severely than the FAA is authorized to do, I'd think fear of dying would be more effective than fear of FAA retribution, but again, unfortunately, the record suggest that it doesn't.:nonod:
I've seen one of those aircraft with the STC that had a placard. You could still technically bring them down to 40, but the placard was clearly placed.

Oh, and yeah, if you significantly break God's rules for the universe, which are NOT random, then you will die...

Ryan
 
I've seen one of those aircraft with the STC that had a placard. You could still technically bring them down to 40, but the placard was clearly placed.
Which STC is that? The ones I know for getting the gross weight increase all call for modifying the flap switch so it won't go past 30.
 
It was an Air Plains 180 hp conversion that I saw a while back. I'm not saying it was legal, :rolleyes: just that I saw it done that way.

Ryan
 
I'm doing some research on that right now. Just got off the phone with Air Plains.

Ryan
 
They told me the person with the answer was on the phone -- probably with you.:D
Seeing how as David and I are friends, I figure I'll get to the bottom of this for him if it would be beneficial. He's already got a sweet plane.

Ryan
 
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