Grumman AA-1B

[Henning]

The places that do these repairs (like True Flight, Fletchair, Excel-Air, Air Mods NW, etc), are pretty good at it, but as you said, for anyone else, it's a lot easier to buy replacement units and bolt them on. Note that you can remove the wings, landing gear, and horizontal stab with only two screwdrivers and three open end wrenches.

Yeah, they are slip,together airplanes, putting one on a trailer only took a couple of hours for a three man crew.

 

[RoscoeT]

What plane does NOT require flying by the numbers?

1.3Vso works in every light single engine airplane I've flown. I've also never flown an airplane that will not bite you if you stall it at 10' above the runway. I've also never flown an airplane that I could not get a feel for stall characteristics after deliberately stalling it one time.

That being said, I think you and Ron are coming from different places. Ron is probably used to instructing student and low time pilots. For experienced pilots who have flown many aircraft types, the Grumman truly is just another type....as most SEL airplanes are.

A very low time pilot who has flown nothing but 172's would likely be in much greater need of Grumman instruction than an experienced pilot who has flown many different types. These discussions are not one size fits all - they are one size fits the lowest common denominator. On the internet, we don't really know who we're talking to, so many err on the side of caution.

 

[docmirror]

First time I flew in a Grumman was solo. I didn't find it a challenging aircraft to any degree. However, like any new type, you're best off from a safety perspective to be trained by someone who understands the type well. Type clubs are a good way to find such a person.

Solo? Pfft. It's a fluffy kitten flown solo.

Go back at gross weight on a hot day, then get back to us.

 

[RoscoeT]

Go back at gross weight on a hot day, then get back to us.

So increased takeoff distance and reduced climb rate = more difficult and dangerous to fly? I don't know how student pilots ever managed to cope with a 152, full fuel, and a bubba instructor.

 

[docmirror]

So increased takeoff distance and reduced climb rate = more difficult and dangerous to fly? I don't know how student pilots ever managed to cope with a 152, full fuel, and a bubba instructor.

If your question was not rhetorical, and was aimed at the plane in question here then - oh hell yes. If, on the other hand you were just being facetious, go find an AA1 and do as I advised. Then get back to us. There's a reason Grumman changed the wing planform, and then added power in later versions. A very good reason.

 

[Grum.Man]

If your question was not rhetorical, and was aimed at the plane in question here then - oh hell yes. If, on the other hand you were just being facetious, go find an AA1 and do as I advised. Then get back to us. There's a reason Grumman changed the wing planform, and then added power in later versions. A very good reason.

The plane still flies the same despite the weight in it. Yea the takeoff roll is longer and climb rate is slower, but I still fly the airplane the same using pretty much the same speeds. Granted I fly mine from elevations in the 1-3k range climbing to no more than 5500 or 6500 feet. I may increase my airspeed a mph or two on rotation to get a more positive rotation, but I still climb out at the book numbers. On landings the only real difference is on hot days at full weight a little jab of the throttle may be needed to arrest the decent rate before the flair. But that is the case in most airplanes.

 

[Grum.Man]

The only discrepancy I have found between doing what the book says and what works in real life is the soft field takeoff procedure. You are better off leaving the nose on the ground until a normal rotation speed is reached than to pick the nose up out of the grass. The induced drag is just too much and once in ground effect it just doesn't like to gain speed.

Flying the hot winged AA1 reminds me a lot of being on a boat. There seems to be a "step" at around 75-80 mph. Get on the back side of this step and you really struggle to regain your composure. Anything past that is like any other airplane. That is the one aspect of a Grumman that I would say is the most different than a Cessna. I haven't flown a piper lately so I can't compare there.

 

[docmirror]

I'll stick with what I've already said on the flying characteristics of the AA1, and lesser to the AA1-B/C. The accident statistics bear it out as well.

All other AA1 pilots/owners operate any way you like. At some point, you're going to have an unpleasant few moments wondering what's happening, because the book says it's all copacetic, and yet, and yet, and yet, those trees/buildings/wires off the end of the runway are getting very big.

<edit: http://www.aviationconsumer.com/sample/AGAC-AA-1.html visit the section on safety, and then conclusions. Don't get me wrong, I like the little plane. Sadly it can't do acro, and I got bored by it in a matter of months. >

 

[Tom-D]

While the wings on my plane were used when I bought them, they were the original wings attached to the used fuselage on which they had been since they left the factory together in 1979. However, I do know of people who have had damaged wings and had them replaced with a used wing off another Cheetah/Tiger (the Cheetah and Tiger wings being identical). You just have to make sure it comes with documentation as to its flight time since new, since the wings have a 12,000 hour life limitation.

Curious ,, are the outer wing panels time lifed? or just the center section? does each section have its own records?

 

[Tom-D]

Yeah, they are slip,together airplanes, putting one on a trailer only took a couple of hours for a three man crew.

The company that came and got my F-24 pulled away with it on the trailer in less than one and half hours. and that is a big aircraft.

It's just a matter of the equipment you have.

 

[poadeleted20]

There's a reason Grumman changed the wing planform, and then added power in later versions. A very good reason.

I think the added power in the AA-1C was more due to the increased empty and gross weights of the C-model than anything else. The original AA-1 and AA-1A were 1500 lb MGW with 108HP, and the AA-1B added 60 lb to the MGW but retained the same 108HP engine, and suffered a slight takeoff/climb performance penalty as a result. The extra 7 HP of the higher compression engine in the AA-1C with its 1600 lb MGW just brought takeoff/climb performance back to about where it had been with the cuffed wing/108HP AA-1A.

BTW, there's an STC from Precision Engine to increase the compression of the original O-235-C2C 108HP engines in the AA-1/1A/1B from 6.7:1 up to 8.5:1, giving you the same power as the 115 HP O-235-L2C in the AA-1C -- it's a good very choice at overhaul time. Air Mods NW also has STC's to increase all AA-1-series engines to 125HP, but some additional airframe mods may be required.

 

[poadeleted20]

The only discrepancy I have found between doing what the book says and what works in real life is the soft field takeoff procedure. You are better off leaving the nose on the ground until a normal rotation speed is reached than to pick the nose up out of the grass. The induced drag is just too much and once in ground effect it just doesn't like to gain speed.

I disagree. The problem is being precise with your pitch attitude control so you just barely lift the nose, or even just lighten it. Leaving the nose down risks getting the nose bounced by a rough spot and catching the prop on the ground -- especially with one of the engine upgrades with a longer prop.

 

[poadeleted20]

Curious ,, are the outer wing panels time lifed? or just the center section?

None of the panels are life limited -- just the tubular spars themselves, so I suppose you could extract the outer spar from the wing ribs and put another one in (although I've never heard of anyone actually doing that). And yes, the outer spars in the wings and the center spar through the fuselage are all life limited -- 12,000 and 12,500 hours, although I can never remember which is which off the top of my head -- not that it's much of an issue given that (other than that small package freight operator which literally flew the wings off a fleet of Cheetahs), even the oldest AA-5x's in private hands are running only about 6000 hours TTAF.

does each section have its own records?

There are no separate records as long as they remain installed -- it's all in the airframe log. If a wing or center spar tube is removed, the mechanic doing the work tags the item with the total time up to removal based on the airframe records and signs the tag. The tag then goes with the part, which is pretty much worthless without the tag so don't lose the tag. The information is then entered into the airframe log of the receiving aircraft by the installing mechanic.

 

[Henning]

The company that came and got my F-24 pulled away with it on the trailer in less than one and half hours. and that is a big aircraft.

It's just a matter of the equipment you have.

Yeah, but we didn't want to damage anything else on this one, it was the parts donor for the other. Loading takes a while.

 

[docmirror]

I think the added power in the AA-1C was more due to the increased empty and gross weights of the C-model than anything else. The original AA-1 and AA-1A were 1500 lb MGW with 108HP, and the AA-1B added 60 lb to the MGW but retained the same 108HP engine, and suffered a slight takeoff/climb performance penalty as a result. The extra 7 HP of the higher compression engine in the AA-1C with its 1600 lb MGW just brought takeoff/climb performance back to about where it had been with the cuffed wing/108HP AA-1A.

BTW, there's an STC from Precision Engine to increase the compression of the original O-235-C2C 108HP engines in the AA-1/1A/1B from 6.7:1 up to 8.5:1, giving you the same power as the 115 HP O-235-L2C in the AA-1C -- it's a good very choice at overhaul time. Air Mods NW also has STC's to increase all AA-1-series engines to 125HP, but some additional airframe mods may be required.

I'm aware of all that. Again, I'm not one to devolve into minutia, and my post was related to a quote asking if the AA1 was more dangerous and difficult. the fact that there are STCs for increased power is also a telling statement to the nature of the standard AA1, but again, didn't want to belabor.

If others want to buy/fly the AA1 variety, my only point is that they are not as forgiving of slight mistakes in operation.

And I'm done here. Fly, don't fly, I have exceeded my 2 cents worth of history with the aircraft.

 

[RoscoeT]

I'm aware of all that. Again, I'm not one to devolve into minutia, and my post was related to a quote asking if the AA1 was more dangerous and difficult. the fact that there are STCs for increased power is also a telling statement to the nature of the standard AA1, but again, didn't want to belabor.

If others want to buy/fly the AA1 variety, my only point is that they are not as forgiving of slight mistakes in operation.

And I'm done here. Fly, don't fly, I have exceeded my 2 cents worth of history with the aircraft.

Or you could have just said, "thanks for the clarification".

 

[Pilawt]

That was a 4-seater, not a 2-seater, and I doubt they built (no less sold) anywhere near the 1800 units that the AA-1-series numbered. That compares to 300 Beech Skippers and 2500 Piper Tomahawks.

See Post 151.

I think the added power in the AA-1C was more due to the increased empty and gross weights of the C-model than anything else.

The reason they switched from the 108 hp O-235-C2C in the AA-1B to the 115 hp O-235-L2C in the AA-1C in 1977 ...

... is the same reason that the Cherokee Warrior switched from a 150 hp O-320-E3D to a 160 hp O-320-D3G in 1977 ...

-- is the same reason that the Cessna 172 switched from a 150 hp O-320-E2D to a 160 hp O-320-H2AD in 1977 ...

-- is the same reason that the Cessna 182 switched to a Continental O-470-U in 1977 ...

-- is the same reason that the 235 hp Cherokee Pathfinder with the O-540-B4B5 ended production in 1977, and when the 235 hp Dakota came out a year and a half later it had a O-540-J3A5D ...

-- and is the same reason that in April 1977 Cessna announced that the Continental-powered Cessna 150 would be replaced with the Lycoming-powered 152.

These aren't coincidences. Anybody remember why? :wink2:

 

[Grum.Man]

I'll stick with what I've already said on the flying characteristics of the AA1, and lesser to the AA1-B/C. The accident statistics bear it out as well.

All other AA1 pilots/owners operate any way you like. At some point, you're going to have an unpleasant few moments wondering what's happening, because the book says it's all copacetic, and yet, and yet, and yet, those trees/buildings/wires off the end of the runway are getting very big.

<edit: http://www.aviationconsumer.com/sample/AGAC-AA-1.html visit the section on safety, and then conclusions. Don't get me wrong, I like the little plane. Sadly it can't do acro, and I got bored by it in a matter of months. >

You must be used to flying at higher density altitudes because that is certainly not the case if operating within the GW of the aircraft. I am a current owner and flyer of an original AA1 which is probably the worst of the worse and never had a pucker moment. I've operated out of 3-4k density altitudes on hot days at gross and it did exactly as the manual said it would.

 

[Tom-D]

Yeah, but we didn't want to damage anything else on this one, it was the parts donor for the other. Loading takes a while.

They didn't cut the 24 apart either.

Disassembled and packed on trailer.

Hour and a half.. this was not their first aircraft either.

 

[Grum.Man]

I disagree. The problem is being precise with your pitch attitude control so you just barely lift the nose, or even just lighten it. Leaving the nose down risks getting the nose bounced by a rough spot and catching the prop on the ground -- especially with one of the engine upgrades with a longer prop.

You are entitled to your opinion but I own an AA1 and you do not. I am speaking from current experience. The grass would need to be pretty high and pretty rough for me to ever lift the nose and try to accelerate in ground effect. The latter a's, b's, and c's may do fine like that but that isn't the way the AA1 should be flown.

The best practice I have found is to hold slight back pressure keeping the nose on the ground. Rotate at 65-70 and add two second of flaps. It will jump off the ground and give you 25 feet or so to work with. Raise the flaps as you accelerate and hold 79 mph for best angle of climb. Gaining that 25 feet allows you to pitch the nose over without settling and gain speed quicker.

 

[docmirror]

You are entitled to your opinion but I own an AA1 and you do not. I am speaking from current experience.

I already said fine with me, and that I've given more than my 2 cents worth.

Seriously doubt the physics of lift have changed since the late 60s. If you don't like my POV, read the link I provided from Aviation Consumer. The only aviation publication that has never accepted revenue from any mfg, so you get the straight dope. If you do choose to read it, and don't like what they have to say, read some of the owner reports at the bottom. Unbiased has a place in the process.

 

[Tom-D]

N
There are no separate records as long as they remain installed -- it's all in the airframe log. If a wing or center spar tube is removed, the mechanic doing the work tags the item with the total time up to removal based on the airframe records and signs the tag. The tag then goes with the part, which is pretty much worthless without the tag so don't lose the tag. The information is then entered into the airframe log of the receiving aircraft by the installing mechanic.

That is an acceptable method IAW 43.10, but it really leaves it up to the installer's integrity.

 

[poadeleted20]

You are entitled to your opinion but I own an AA1 and you do not. I am speaking from current experience.

And I've been flying them for 45 years, starting with s/n 12 back in 1970.

The best practice I have found is to hold slight back pressure keeping the nose on the ground. Rotate at 65-70 and add two second of flaps. It will jump off the ground and give you 25 feet or so to work with. Raise the flaps as you accelerate and hold 79 mph for best angle of climb. Gaining that 25 feet allows you to pitch the nose over without settling and gain speed quicker.

You're entitled to do it your way, but I've done some testing on this, and found the added drag of those flaps reduces your acceleration.

 

[poadeleted20]

That is an acceptable method IAW 43.10, but it really leaves it up to the installer's integrity.

I'd say that's pretty much true of any situation where parts are installed, or, for that matter, when any maintenance, repair, or alteration is performed. However, absent that documentation, the next annual by an honest IA will ground the aircraft until the issue is resolved.

I've seen that happen with a Tiger where someone put on a wing off another Tiger without any documentation of the time on the wing. The airplane eventually got to Grumman expert Bill Scott for an annual, who informed the owner as gently as possible that the aircraft was not legal to fly without knowing the history on the wing. It took Bill (with help from David Fletcher at Fletchair) over a year, but they managed to trace down the records on the plane from which the wing had been taken, as well as the mechanics who'd removed the wing from the original plane and installed it on the current plane, and document the hours on it. With that done, Bill was able to return the airplane to service, but it wasn't easy and could have turned out much worse.

 

[Tom-D]

I'd say that's pretty much true of any situation where parts are installed, or, for that matter, when any maintenance, repair, or alteration is performed. However, absent that documentation, the next annual by an honest IA will ground the aircraft until the issue is resolved.

Bad maintenance practices are pretty easy to spot, A wing removal might not be.

I've seen that happen with a Tiger where someone put on a wing off another Tiger without any documentation of the time on the wing. The airplane eventually got to Grumman expert Bill Scott for an annual, who informed the owner as gently as possible that the aircraft was not legal to fly without knowing the history on the wing. It took Bill (with help from David Fletcher at Fletchair) over a year, but they managed to trace down the records on the plane from which the wing had been taken, as well as the mechanics who'd removed the wing from the original plane and installed it on the current plane, and document the hours on it. With that done, Bill was able to return the airplane to service, but it wasn't easy and could have turned out much worse.

I'd have few questions about the all log book entries on that aircraft. When they didn't comply with 43.10 with all the times and tracking required,on a spar, why would they do anything any better.

This is one topic I harp on all the time, log book entries, what should be in them. and a lot of pilots don't have a clue.

 

[poadeleted20]

Bad maintenance practices are pretty easy to spot, A wing removal might not be.

The factory put a number of markings on the wings showing which plane they were attached to when it left the factory. In any event, in the case I described, the mechanic properly logged the replacement work, just not the time on the wing, so it was not a case of a sneaked-on wing.

This is one topic I harp on all the time, log book entries, what should be in them. and a lot of pilots don't have a clue.

Agreed. I push it a lot when working with folks new to aircraft ownership.

 

[Grum.Man]

And I've been flying them for 45 years, starting with s/n 12 back in 1970.

You're entitled to do it your way, but I've done some testing on this, and found the added drag of those flaps reduces your acceleration.

As have I and have found my horizontal distance to clear a 75' obstacle is on average 100' shorter using the method I have described. Free of charge I might add.

 

[poadeleted20]

As have I and have found my horizontal distance to clear a 75' obstacle is on average 100' shorter using the method I have described. Free of charge I might add.

I thought we were talking about soft-field takeoffs, not short-field.

But if you're talking short-field, I've done a good bit of testing personally and as well as observing many Grumman pilots regarding the use of flaps to improve takeoff performance on short fields. The reason many pilots achieve a shorter distance with flaps in a Grumman is that they do not rotate to the proper Vx attitude at liftoff, generally because they see the attitude as being too steep (about 12 degrees nose up). Instead, they usually stop about 7-9 degrees nose up, so they accelerate significantly past Vx, and climb rate and climb angle both decreases. When flaps are added, half the wing has about 5 degrees more angle of attack, and they get more lift at the same pitch attitude, so climb rate and climb angle both increase. However, if they leave the flaps down and pitch the entire wing to the proper AoA, they get even more lift than before and climb rate and climb angle after liftoff both improve further.

The reason this is all true is that unlike the Cessnas with their long-chord slotted Fowler-type flaps, the coefficient of lift on this wing changes very little with the short-chord straight flaps with which Grummans are equipped. As a result, about all the flaps on a Grumman do is add drag and reduce deck angle at the same net lift coefficient -- note how small the difference in stall speed is flaps up vs flaps down (and compare that with the much larger difference on a C-150/152/172). Pilots who never really learned how the different types of flaps operate and what they accomplish tend to misuse them in this situation.

 

[Henning]

I guess y'all work a lot faster up there in the cold than we did in the triple digit Texas heat.

 

[kgruber]

See Post 151.



The reason they switched from the 108 hp O-235-C2C in the AA-1B to the 115 hp O-235-L2C in the AA-1C in 1977 ...

... is the same reason that the Cherokee Warrior switched from a 150 hp O-320-E3D to a 160 hp O-320-D3G in 1977 ...

-- is the same reason that the Cessna 172 switched from a 150 hp O-320-E2D to a 160 hp O-320-H2AD in 1977 ...

-- is the same reason that the Cessna 182 switched to a Continental O-470-U in 1977 ...

-- is the same reason that the 235 hp Cherokee Pathfinder with the O-540-B4B5 ended production in 1977, and when the 235 hp Dakota came out a year and a half later it had a O-540-J3A5D ...

-- and is the same reason that in April 1977 Cessna announced that the Continental-powered Cessna 150 would be replaced with the Lycoming-powered 152.

These aren't coincidences. Anybody remember why? :wink2:

I know! I know! I know! But I'm NOT TELLING!

 

[asechrest]

Note to self: If facing Pilawt on Jeopardy and the Final Jeopardy category is "GenAv Aircraft History", forfeit the contest.

 

[asicer]

See Post 151.



The reason they switched from the 108 hp O-235-C2C in the AA-1B to the 115 hp O-235-L2C in the AA-1C in 1977 ...

... is the same reason that the Cherokee Warrior switched from a 150 hp O-320-E3D to a 160 hp O-320-D3G in 1977 ...

-- is the same reason that the Cessna 172 switched from a 150 hp O-320-E2D to a 160 hp O-320-H2AD in 1977 ...

-- is the same reason that the Cessna 182 switched to a Continental O-470-U in 1977 ...

-- is the same reason that the 235 hp Cherokee Pathfinder with the O-540-B4B5 ended production in 1977, and when the 235 hp Dakota came out a year and a half later it had a O-540-J3A5D ...

-- and is the same reason that in April 1977 Cessna announced that the Continental-powered Cessna 150 would be replaced with the Lycoming-powered 152.

These aren't coincidences. Anybody remember why? :wink2:

Can I have 100 guesses, starting with the Least Likely?

 

[Pilawt]

Can I have 100 guesses, starting with the Least Likely?

Yes, but the first 80 don't count, and that might leave you seeing red.

 

[jsstevens]

See Post 151.



The reason they switched from the 108 hp O-235-C2C in the AA-1B to the 115 hp O-235-L2C in the AA-1C in 1977 ...

... is the same reason that the Cherokee Warrior switched from a 150 hp O-320-E3D to a 160 hp O-320-D3G in 1977 ...

-- is the same reason that the Cessna 172 switched from a 150 hp O-320-E2D to a 160 hp O-320-H2AD in 1977 ...

-- is the same reason that the Cessna 182 switched to a Continental O-470-U in 1977 ...

-- is the same reason that the 235 hp Cherokee Pathfinder with the O-540-B4B5 ended production in 1977, and when the 235 hp Dakota came out a year and a half later it had a O-540-J3A5D ...

-- and is the same reason that in April 1977 Cessna announced that the Continental-powered Cessna 150 would be replaced with the Lycoming-powered 152.

These aren't coincidences. Anybody remember why? :wink2:

It's the year I graduated form high school? Naw, that's probably not it.

What's fueling this debate?

John

 

[Anthony]

It's the year I graduated form high school? Naw, that's probably not it.

What's fueling this debate?

John

LOL! 100LL.

 

[jdennis1989]

Wow, looks like there's been quite a lot of debating since I last checked on this haha.

Well I test flew it last weekend with the owner. I love the plane. I think I have my financing lined up, and I will be looking at nailing down insurance Monday. The owner wants me to go flying with him tomorrow again. It's supposed to be nice weather, so it's hard to turn him down.

 

[jdennis1989]

The current owner is under the assumption that I will have to have a CFI actually check me out for insurance. Is this true?

 

[jesse]

The current owner is under the assumption that I will have to have a CFI actually check me out for insurance. Is this true?

You'll know when you talk to the insurance company. Typically for most types unless you have 25 in type in the last year or so they'll want you to do X time with a CFI. It won't be many hours and the requirements for what instructor you need will be very basic.

 

[Tom-D]

The current owner is under the assumption that I will have to have a CFI actually check me out for insurance. Is this true?

Unless the current owner is your insurance company, they don't have much to say about it.


And no it's not.

call your insurance agent find out what they really need .

 

[poadeleted20]

Unless the current owner is your insurance company, they don't have much to say about it.


And no it's not.

The reality is exactly what the owner told the poster and what Jesse said -- generally speaking, insurance companies will require a check with an instructor unless you have some number of PIC hours in the Grumman type you'll be insuring with them. How many hours in type will waive that, and the qualifications of the instructor for the checkout vary between insurers and the overall experience of the pilot involved.

call your insurance agent find out what they really need .

Now that is good advice.