Looking for Perspective on Aircraft Not Approved for Spins

kontiki

kontiki

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Kontiki
I'm still on the fence on what to buy for first airplane.

Had a great day flying with a friend sitting next to me. Not sure I would have had the same fun with her sitting in the back of a Citabria.

So I was looking at the Grumman American. Friends point out that Grumman American is not approved for spins because they may be unrecoverable.

Just how much of a concern is that?

Sure, not good for an aerobatics airplane, but do owners consider it a problem?

I know some aircraft like that have a BRS, it that really neccessary or are there aerodynamic or marketing issues that drive that.

Thanks for all shared insights.
 
No big deal, just don't try to spin it... If it snapped into an unrecoverable spin due to an un-coordinated power on stall they wouldn't certify it.
 
kontiki said:
So I was looking at the Grumman American. Friends point out that Grumman American is not approved for spins because they may be unrecoverable.
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That's not exactly true. They were never tested for recovery beyond the 1-turn/3-second spin test required for certification without approval for intentional spins, but they recovered just fine from those. FWIW, that's the same standard, level of certification, and placarding as a Piper Warrior/Archer, a Cessna 182 and a Beech Bonanza. Also, there is documentation of someone (a recent US Navy Test Pilot School graduate with more testosterone than judgement) intentionally (and illegally) spinning an AA-1 Yankee, and recovering it after letting the spin fully develop through three full turns. However, I would recommend in the strongest possible terms against attempting to duplicate his feat.

Just how much of a concern is that?
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No more of a concern than it is for the very popular abovementioned airplanes.

Sure, not good for an aerobatics airplane, but do owners consider it a problem?
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After over 2500 hours in Grummans, not at all.

I know some aircraft like that have a BRS, it that really neccessary or are there aerodynamic or marketing issues that drive that.
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The Cirrus has the BRS because the man who started the company was seriously injured nearly died after the very light plane he flying (can't remember if it was an ultralight or an Experimental-Amateur Built) had a structural failure in flight. The Cirrus was undergoing the spin testing necessary for normal "spins prohibited" certification just like those other planes I mentioned when the FAA approved an exemption from spin testing based on the BRS installation. Being able to stop the testing (which was completely successful to that point) without completing it saved Cirrus a bunch of time and money in its certification program.

So installation of the BRS is definitely a marketing issue for Cirrus, and there are no known aerodynamic issues (and none suspected beyond what is known) driving its inclusion on that plane.
 
Ron Levy said:
The Cirrus has the BRS because the man who started the company was seriously injured nearly died after the very light plane he flying (can't remember if it was an ultralight or an Experimental-Amateur Built) had a structural failure in flight.
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Their rationale is on this web site:

http://www.whycirrus.com/engineering/stall-spin.aspx
"Despite some suggestions to the contrary, CAPS was an integral part of the Cirrus SR20 development from initial conception. Cirrus Co-founder Alan Klapmeier was inspired after surviving a mid-air collision early in his flying career. He wanted the SR20 to have some form of life saving device for when the pilot lost control of the airplane. Even in the mid-nineteen nineties, Cirrus saw parachutes proving themselves in the ultra-light arena and ready to be applied to heavier airplanes."
​
The Cirrus was undergoing the spin testing necessary for normal "spins prohibited" certification just like those other planes I mentioned when the FAA approved an exemption from spin testing based on the BRS installation. Being able to stop the testing (which was completely successful to that point) without completing it saved Cirrus a bunch of time and money in its certification program.

So installation of the BRS is definitely a marketing issue for Cirrus, and there are no known aerodynamic issues (and none suspected beyond what is known) driving its inclusion on that plane.
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To confirm that some spin testing was done, this is a quote again from the above link:
"The European authorities (initially JAA, later EASA) when first evaluating the Cirrus SR20 agreed with the principles of the FAA/ELOS approach but had some further questions. A series of spins was performed on their initiative. While not a complete formal program they reported no unusual characteristics."
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(ELOS: Equivalent level of safety.)
 
When an airplane is placarded against intentional spins, it is likely because the manufacturer elected not to spend more R&D money on intensive spin testing beyond the basic certification standard. For example, while the Cessna Skycatcher was still under development Cessna posted this on its website:
Cessna is still gathering input from customers on whether to eventually approve the SkyCatcher for intentional spins. To be approved for intentional spins, the ASTM standard for light sport aircraft requires that the aircraft “be able to recover from a three-turn spin in not more than one and one-half additional turns.” This will require a much larger flight-test spin matrix and, if pursued, will be done after the initial ASTM compliance for the SkyCatcher is complete.​
 
It shouldn't be a big worry if you aren't going to go do spins. Most people get into stall/spin scenarios because of uncoordinated flight from base to final. Keep flying airspeed and coordinated flight and this will not happen to you.
 
What really kills everyone in the base-to-final spin is the lack of altitude, no matter how aerobatic the airplane is. Might as well fly an unrecoverable airplane, the result is exactly the same. Recoverability only makes the difference if you spin while at altitude. Therefore, the question is: how easy it is to spin in from a cruise? I often find myself drifting off course or rolling when I start digging in the flight bag for a snack. I have not stalled at 10.5k yet, but...
 
Also, what catagory is the Grumman in? IIRC If "Normal" it can't be spun as a matter of regulation. Just like a 172 with someone in the back seat, as "Utillity" operations in it require an empty rear seat and a lighter gross.
 
Skylane81E said:
Also, what catagory is the Grumman in? IIRC If "Normal" it can't be spun as a matter of regulation. Just like a 172 with someone in the back seat, as "Utillity" operations in it require an empty rear seat and a lighter gross.
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Like the 172, Grummans are dual certified in Normal and Utility, depending on loaded weight and cg.
 
..and Utility does not always mean spin. The Bonanza is certified utility anywhere in it's W&B envelope but is not spin approved. I suppose the aerobatic version is, but I don't know anything about them, given how rare they are.
 
jesse said:
..and Utility does not always mean spin. The Bonanza is certified utility anywhere in it's W&B envelope but is not spin approved. I suppose the aerobatic version is, but I don't know anything about them, given how rare they are.
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So is the Piper Warrior...you could fly it in the Utility category (albeit at a lower MGW), and intentional spins were still prohibited.
 
Why exactly are you concerned?

Having an aircraft approved for intentional spins doesn't really mean that much. Just Look at the Piper Tomahawk.
 
I think I have what I need. It's really great to be abe to tap into X years of diverse experience for questions like this.

The person at work sounds like an experienced pilot/electrical engineer, very smart and diverse, nice enough chatty guy, now inactive as a pilot. He likes talking about spins, maybe because is segways nicely into his own CFI spin recovery story (one I've heard at least 3 times now). So it goes with people.

I'm just trying to sort out what's usefull for me. I'm off to the field. Really, thanks for all the insights.

Bruce
 
kontiki said:
I think I have what I need. It's really great to be abe to tap into X years of diverse experience for questions like this.

The person at work sounds like an experienced pilot/electrical engineer, very smart and diverse, nice enough chatty guy, now inactive as a pilot. He likes talking about spins, maybe because is segways nicely into his own CFI spin recovery story (one I've heard at least 3 times now). So it goes with people.

I'm just trying to sort out what's usefull for me. I'm off to the field. Really, thanks for all the insights.

Bruce
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If you want to practice spins or try any aerobatic maneuver (at which point you should be well versed in spin recovery) you need a plane that has proven spin recovery characteristics. Otherwise it really doesn't matter. I fly an airplane that has just the opposite, i.e. a track record of unrecoverable spins yet it's just as safe or safer than a C172 flown in the utility category as long as I avoid spins (which is pretty easy to do). And in the hands of any pilot who blunders into an inadvertent spin at low altitude, an airplane with the most positive spin recovery characteristics isn't going to save the day.

Looking for an airplane to have good spin recovery characteristics to be "safer" for non-aerobatic flying is a lot like looking for one that can tolerate 10g without the wings coming off to make you safer in the traffic pattern. Normal flight never requires more than 2-3 g nor does it require spin recovery. Don't pull more than 2 g and don't spin and it just won't matter.
 
Lance said it well - you really don't have any need for a spin-approved aircraft. I've only flown one spin-approved aircraft, and that's the only aircraft I've ever spun. It was also intentional.

Just don't spin the plane - which really isn't hard.
 
I don't have any experience with the Grumman American, but I have spun aircraft few different airplanes. DA40 is not certified for spins and I did get a chance to spin it (I'm not proud of that). I'm not going to say that it was very easy to recover but it was certainly not difficult.
The way I see it is most single engine airplanes should be recoverable. I wouldn't be too concerned about spinning the Grumman unless it has a history of not recovering (which I'm pretty sure it does not).
 
kontiki said:
I'm still on the fence on what to buy for first airplane.

Had a great day flying with a friend sitting next to me. Not sure I would have had the same fun with her sitting in the back of a Citabria.

So I was looking at the Grumman American. Friends point out that Grumman American is not approved for spins because they may be unrecoverable.

Just how much of a concern is that?

Sure, not good for an aerobatics airplane, but do owners consider it a problem?

I know some aircraft like that have a BRS, it that really neccessary or are there aerodynamic or marketing issues that drive that.

Thanks for all shared insights.
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Over 20 years and 2000hrs of all sorts of flying in all sort of airplanes and I never accidentally broke into a spin. If the plane fits my budget and mission, not being certified for intentional spins would not even cross my mind.
 
If you want to do spins get one that is approved for it. Otherwise push the nose down when you stall.

Sent from my SPH-D700 using Tapatalk
 
Contributing to the OWT about Grumman spin characteristics is the old video floating around of a NASA spin test of the prototype American Aviation AA-1 Yankee in the 1970s. What is not often mentioned is that the test airplane was modified to explore the outer edges of spin aerodynamics, not necessarily to evaluate the Yankee itself. In fact, according to an AOPA Air Safety Foundation article, the NASA study compared spin recovery in the Yankee to the Piper Arrow:
But recovery from a spin is a far different matter, and takes much more altitude, even with skilled pilots. A NASA study done in the late 1970s proved that the average altitude loss in spins done with a Grumman American AA-1 (Yankee) and a Piper PA-28R (Arrow), two popular single-engine aircraft, was nearly 1,200 feet. (It should be noted that neither aircraft is approved for spins, but NASA was testing them for possible improvements in spin handling characteristics.)

In the Yankee, it took an average of 210 feet for entry, 340 feet for stopping the turn, and another 550 feet for recovery, for a total of 1100 feet. In the Arrow, the figures were 140 feet for entry, 400 feet for stopping the rotation, and 620 for recovery, for a total of 1160 feet.
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In 1978 Grumman American advertised a "spin package" option (fuselage strakes and ventral fin, as shown on N1551R in the photo below) for the AA-1C Lynx, but I don't know if any airplanes were delivered to customers with this option.


aa-1b_t-cat.jpg


I would expect the spin characteristics of the AA-5 series, with its different airfoil, larger tail surfaces and many other changes, to be quite different from those of the original AA-1 Yankee.
 
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If it's not approved for intentional spins make sure all your spins are unintentional.
 
Pilawt said:
In 1978 Grumman American advertised a "spin package" option (fuselage strakes and ventral fin, as shown on N1551R in the photo below) for the AA-1C Lynx, but I don't know if any airplanes were delivered to customers with this option.
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Never certified, no less delivered. Ken Blackman at Air Mods NW probably knows more about this than anyone else around.
 
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