Better for Basic Aerobatic Instruction, 8KCAB-180 or 7KCAB-150?

they still advertise the 7gcaa as available. just add inverted fuel and oil and it's a 7kcab.
 
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Bartman said:
they still advertise the 7gcaa as available. just add inverted fuel and oil and it's a 7kcab.
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It's a different engine. I guess the rationale is that if someone really wants to fly inverted - they surely would prefer the super D - in order to have a wing that flies upside down to go with the engine. Having the complexity of fuel injection and the inverted oil system with the flat bottomed wing makes limited sense - I think most people would prefer either the GCAA or the 8KCAB - not one in between. There are lots of 7ECAs that were converted to 7GCAA - but I've not seen one converted to the 7KCAB, although equally feasible with the type certificate
 
Great discussion… very educational for a newbie!
I’ve just completed flying the 20 hours needed for break-in on my engine and am picking it up this morning after the oil change and prop balance. I can’t wait to get started really learning the plane with short / soft field practice and some stall / spin training. Then, on to loops and rolls!
 
volvo164 said:
It's a different engine. I guess the rationale is that if someone really wants to fly inverted - they surely would prefer the super D - in order to have a wing that flies upside down to go with the engine. Having the complexity of fuel injection and the inverted oil system with the flat bottomed wing makes limited sense - I think most people would prefer either the GCAA or the 8KCAB - not one in between. There are lots of 7ECAs that were converted to 7GCAA - but I've not seen one converted to the 7KCAB, although equally feasible with the type certificate
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you're right, the engine is different so no longer as simple as just adding inverted oil/fuel components.
now, how about a clipped wing 7KCAB to make it more nimble and a better competitor against all of those pesky 8KCAB's???? :slap:
 
Halhayden said:
Great discussion… very educational for a newbie!
I’ve just completed flying the 20 hours needed for break-in on my engine and am picking it up this morning after the oil change and prop balance. I can’t wait to get started really learning the plane with short / soft field practice and some stall / spin training. Then, on to loops and rolls!
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You sound like a man with a plan. Any chance you're going to try competing with it?
 
@Bartman , I appreciate this thread. This was the main question I was looking to get some insight on. I am a CFI, and got my tailwheel in a Super Decathlon. I also have some hours in a few different RVs (mostly RV-8). Anyway, I get asked almost weekly if I can give someone some tailwheel training. Also I have had folks ask for upset recovery, or spin endorsements (frequently).

I haven't done much in the way of aerobatics, but I wouldn't mind doing and teaching some basic maneuvers, but I have only done those in an RV-8 at this point).

Anyway, I have been looking for the 'right' airplane for that mission, and to supplement my training business. Sounds like the 7KCAB might fit the bill. Because I only have time in an 8KCAB, I was looking there. But this thread is pushing me toward a 7KCAB. Thanks!
 
Hi Nathan,

Funny you brought this back up, I was on another forum site this week where Budd Davisson (www.airbum.com) hangs out and the Super Decathlon came up. Budd was saying that a 150 hp Citabria will out-climb a 180 hp Super Decathlon which I haven't personally confirmed but Budd owned a Super D and has a lot of time in an awful lot of airplanes so I'm inclined to believe him. A flat bottom wing is better at making lift and will do so with less drag, generally speaking, so I can see how it would be true.

The Super D has a nearly symmetrical wing. What that does over the flat bottom wing of the Citabria is that it allows outside maneuvers. It also allows the plane to fly at a more level attitude when inverted. But if you're just learning then neither of those things is really important so the 7KCAB being more economical to operate and maintain makes it a better plane to own and instruct with, IMHO. Basic spin training, tail wheel checkouts, upset recovery training......it can all be done just as effectively in the 7KCAB with lower operating costs than in the 180 hp 8KCAB.
 
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For all that, consider a 115 hp 7ECA. If you are trying to make a living instructing, the reduced fuel burn will become meaningful for the bottom line; it will do everything a 7KCAB will do except inverted flight, and will be a better trainer for tailwheel transition.
 
IMO the 7KCAB load limits make it less suitable as an aerobatic trainer. The TCDS says not to exceed -2.0G, and not to exceed 135mph during negative G's. It is fairly easy to push -2G momentarily when learning rolls and inverted flight. Let the nose drop a bit during half roll to inverted, pick up speed, then push forward to get back on the horizon, and you have just overstressed the aircraft. Pulling it out of service to inspect each time that happened could be a big negative for a commercial operation like a flight school.

I noticed several times this spring after practicing that I had pushed -2G, and that was without any outside maneuvers.

8KCAB load limits of +6/-5G provide significantly more margin of error. You are not going to bend a Decathlon, no matter how bad you bungle a maneuver. IMO a better fit for a training environment.
 
I believe the tail incidence on an 8KCAB is different than a Citabria. there isn't enough down elevator to push -2 g's. I am full forward stick through inverted when rolling and the nose is still not high enough.

haven't ever seen -2 g's in the acro I have done over the last year.
 
I was responding to the poster who wants to do tailwheel checkouts, spin training, and limited aero. The Decathlon is a lousy taildragger trainer - the Citabrias are much better. And if all you want is a loop and an aileron roll, the ECA does a very nice job of that.
If your primary goal is tailwheel checkouts, the J3 is the best.
Opinion.
 
Well, owning a 7ECA, I mentioned that I'm considering a 7KCAB. I'm sure it would be better at acro from a competition perspective, but not necessarily just to do it for fun or training. I was looking at the performance numbers carefully - and I know lot of people advocate for the bigger engine, and then claiming to be able to throttle it back. But in no scenario will it actually beat a 7ECA in terms of fuel efficiency - and for sure legal useful load. So now I'm not so sure if I want to move up - as I'm able to use the 7ECA for 3+ hour cross countries, 2 adults, and a lot of luggage. Yes, with a headwind we watch the cars pass us on the highways, but oh well ... we've got a nicer view! For combined tail/acro/ upset training purpose - I would think the 7ECA is the best bet. If you're not going to let the student fly it solo acro, than the fixed pitch prop should not be an issue (and big benefit from weight and cost saving). Learning new maneuvers on my own, I do occasionally red line it (or even after not flying acro for a few weeks, you get rusty quickly), and I always kick myself for it, but my prop still seems straight ...
 
There are ways to insure an aircraft for solo rental, but hold on to your hat - my insurance on the instructional Cub is four times as expensive as my personal Cub, and I am restricted to ten students per year. And after the third student they hit me with 10% for each additional - and even worse, my CFI insurance doesn't work, and to be covered while instructing I had to transcribe a verbal assurance - they wouldn't put it in writing! And worse yet, the students are "additional insured" meaning if something happens while I am instructing my liability coverage is cut in half!

I have over 5000 hours in Cubs, but one insurer turned me down for a J5 - not enough time in type. It is a whole new world out there. PA-12 time doesn't count.
 
I know I'm late to the discussion but my here's my experienced $0.02. I'm arriving with the been there done that perspective. I operated a training operation with both a 7ECA and a 7KCAB in addition to a Great Lakes. I've got time in the Decathlons and personally wouldn't own one in favor of the better all around workhorse 7KCAB which doesn't mean I would kick a Decathlon out of bed either. You know, if the price is right.. The 180 decathlon has a slightly better roll rate and can push harder negative. Beyond that the 7KCAB has better field performance and can do everything most people care to do. I don't know many people who truly enjoy outside loops. The 7KCAB is perfectly happy doing rollers. Neither is suitable for inverted spin training which true aerobatic training facility needs to have. The 7ECA has the best control feel of the lot and useful load. Their only issue is climb performance. The 7ECA is fully capable of flying sportsman without taking a break in the right hands. I tried very hard to fly intermediate with the 7KCAB which has a couple of limits, primarily doing snaps on any down line.

To address the blue collar flight instruction business plan using the 7KCAB. I've done it and Dreamcatcher Aviation is coming back in the near future with a 7KCAB followed by another one and a 7ECA. Provided I can manage the funds. I'm currently instructing in OPA's. As was mentioned, the plain Jane Citabria is a wonderful airplane for tailwheel training and is fully capable of being a good basic aerobatic instruction planform. The caveat there is that any student truly interested in going very far in aerobatics needs spin training to include inverted spin recovery. End of the day, the differences between Decathlon and Citabria are minor compared with the difference of either to a Pitts, Lakes, Laser, Skybolt, Extra or other full bread acro steed and either is good for which ever one you like better.

My resume is my youtube channel which has the same username as here.
 
Feman43 said:
I know I'm late to the discussion but my here's my experienced $0.02. I'm arriving with the been there done that perspective. I operated a training operation with both a 7ECA and a 7KCAB in addition to a Great Lakes. I've got time in the Decathlons and personally wouldn't own one in favor of the better all around workhorse 7KCAB which doesn't mean I would kick a Decathlon out of bed either. You know, if the price is right.. The 180 decathlon has a slightly better roll rate and can push harder negative. Beyond that the 7KCAB has better field performance and can do everything most people care to do. I don't know many people who truly enjoy outside loops. The 7KCAB is perfectly happy doing rollers. Neither is suitable for inverted spin training which true aerobatic training facility needs to have. The 7ECA has the best control feel of the lot and useful load. Their only issue is climb performance. The 7ECA is fully capable of flying sportsman without taking a break in the right hands. I tried very hard to fly intermediate with the 7KCAB which has a couple of limits, primarily doing snaps on any down line.

To address the blue collar flight instruction business plan using the 7KCAB. I've done it and Dreamcatcher Aviation is coming back in the near future with a 7KCAB followed by another one and a 7ECA. Provided I can manage the funds. I'm currently instructing in OPA's. As was mentioned, the plain Jane Citabria is a wonderful airplane for tailwheel training and is fully capable of being a good basic aerobatic instruction planform. The caveat there is that any student truly interested in going very far in aerobatics needs spin training to include inverted spin recovery. End of the day, the differences between Decathlon and Citabria are minor compared with the difference of either to a Pitts, Lakes, Laser, Skybolt, Extra or other full bread acro steed and either is good for which ever one you like better.

My resume is my youtube channel which has the same username as here.
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i love you man! lol i want to hear more about being in the business with two Citabrias!
 
Big Ed said:
Why?
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Because inverted spins happen easily from botched maneuvers. A botched roll or hammer head can readily develop in an inverted spin. The first inverted spin I was in was inadvertent and the instructor teaching had never been in or recovered from one either. The altitude margin during that event was approximately 5 feet from an initial 2500. When the airplane stalled inverted and began spinning he was as disoriented as I was. Along the way, after two or three turns the airplane crossed over into an upright spin which I had been taught to recover from. Inverted spins are massively disorienting.

Two qualifying questions for any instructor to determine if they are indeed qualified. First, can you recover from an inverted spin. Second can you teach me to recover from inverted spins. A no response to either question is a disqualification.

I haven't had two Citabrias operating simultaneously at once. My biggest operation was a Citabria 7ECA, Travel Air and a Great Lakes. The 7 KCAB was at a later time frame.
 
I did a couple inverted spins way back when, in a 7KCAB. I asked, and the instructor said sure. Did not seem difficult.

Once you stop the rotation and draw a down line, recover either way. I prefer positive G pull outs.

In a similar vein, i tried a couple solo outside loops. Last quarter I simply pulled out rightside up. Now I don't even do outside loops - an occasional Immelman is good enough for me.

But then, I do not teach aero - at most I would have a student do spins before solo, and an aileron roll and loop before Private. No more - as I tell my friends, I personally couldn't pass a six hour oral on aviation related subject matter, and would not expect that from a student either. My ATP oral was an hour - my Airbus oral lasted 15 minutes - and I think my MS oral was 45 minutes. So not teaching primary.

Still doing eight taildragger endorsements per year (max allowed on the insurance).
 
Feman43 said:
Because inverted spins happen easily from botched maneuvers. A botched roll or hammer head can readily develop in an inverted spin. The first inverted spin I was in was inadvertent and the instructor teaching had never been in or recovered from one either. The altitude margin during that event was approximately 5 feet from an initial 2500. When the airplane stalled inverted and began spinning he was as disoriented as I was. Along the way, after two or three turns the airplane crossed over into an upright spin which I had been taught to recover from. Inverted spins are massively disorienting.

Two qualifying questions for any instructor to determine if they are indeed qualified. First, can you recover from an inverted spin. Second can you teach me to recover from inverted spins. A no response to either question is a disqualification.

I haven't had two Citabrias operating simultaneously at once. My biggest operation was a Citabria 7ECA, Travel Air and a Great Lakes. The 7 KCAB was at a later time frame.
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No, my question was why do you say a Decathlon is unsuitable for inverted spin training?
 
Big Ed said:
No, my question was why do you say a Decathlon is unsuitable for inverted spin training?
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The windshield has blown in on a couple of them and factory recommends against it. Not saying it can't be done just not advisable which puts it outside of suitable for training. The corollary is that any instructor who is teaching aerobatics needs to be fully capable of recovery from inverted spins and teaching inverted spin recovery. I know it is a position in opposition to many but it comes from having been in the aerobatic training community and having experienced an instructor who was incapable. In my personal instance my back seater was just a passenger from the time the inverted stall progressed into the spin. I was fortunate the airplane transitioned to an upright spin which I had been trained to recover from prior to soloing.
 
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