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

Bartman

Bartman

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Chalk this up to me daydreaming in the shower, wondering which would be better for a small operation with a couple of airplanes doing upset training, tailwheel checkouts, and some basic to intermediate aerobatic courses.

I was kind of wondering why the 7KCAB isn't the hands down favorite for basic aerobatic instruction, it's less expensive to operate and purchase and has all of the moxy to do what beginner/Primary/Sportsman students need. The Super Decathlon has the HP to haul two students straight up or up and over a loop but that isn't to say it can't be done in the 7KCAB.

So, you're starting a for-hire training operation. Which do you choose?

Go!
 
The 8KCAB with 150 C/S. The only better one would be the same converted to 160.

I don't teach acro (except for rolls now and then) but own a 180 Decathlon. I'd trade it even for a 160. It is a very nice aircraft, and I am happy with it - 18 years in.
 
Bob,

I should know better than to argue with you but I'd bet the lower costs of a fixed pitch prop and the flat bottom wing will make for a better all around mount. The symmetrical wing is great for inverted flight and tracing nice figures through the sky but for instruction, is that really necessary?

Maybe I should have included the 150 hp, fixed pitch Decathlon in the discussion but that plane wouldn't climb as well as the 7KCAB for getting up and to the practice zone.

Fixed pitch vs. constant speed, most of your homebuilt biplanes that are very common and competitive at aerobatic contests are fixed pitch. Constant speed is nice but if the cost to keep it maintained is coming from a low-margin, high overhead operation, is it necessarily best for the business? Doesn't the need to monitor engine RPM teach students more as they're in and out of figures?

Discuss.

(don't you hate it when people post something and then write "discuss"? it's a peeve of mine! lol)
 
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I haven't noticed anything peculiar about the C/S prop. I do know that the 150 and 180 both burn 9 1/2-10 gph, ant the 160 only slightly more than 7 1/2.

I trained in a 7 KCAB, then flew my first contest in a Decathlon (here, kid, it flies just like the Citabria - have fun and leave the prop at 25). Considering, I suppose the Citabria was a good trainer, because I got third place, beating out Pitts Specials and Stevens Acros (whatever they were).

If you want to teach taildragging, the Decathlon is not it. If you want to teach acro, I think the symmetrical wing helps, especially inverted.

But ok, 160 hp, fixed pitch. Much lighter.
 
For upset training the extra drag of the Citabria wing helps keep the speed from building so quick. For tailwheel training also the Citabria. For aerobatic training hands down the Decathlon. Just my humble opinion.
 
Joe, I'll have to dig out my airfoils book to see which is more draggy but I'd be curious to see how far behind a 7KCAB with a climb-biased prop would be climbing against a 180hp 8KCAB. The 8KCAB would be near max gross, the 7KCAB too but the 7's max gross is 150 lbs lighter than the 8's.
 
The Super Decathlon is just more suitable for aerobatics than it's predecessors, because it was developed from them for that purpose. The Citabria can do basic maneuvers, but you are always going to be fighting the airplane. It's not just the airfoil and prop. The Decathlon has a shorter, wider wing with zero dihedral and an aileron system with greater mechanical advantage, which improves roll rate and reduces stick force. It also has a much thicker spar and is stressed to a higher G rating. All of these things make it a more suitable platform for instruction, IMO.

Students make mistakes, and acro mistakes can end badly. A stronger spar and a prop that protects the engine from damage due to overspeeding are both useful attributes.

For taildraggery training, a Champ or 7ECA is more than sufficient, and probably better than a Decathlon. Older Decathlons are overly susceptible to prop strikes IMO, because the gear legs were not upgraded as the weight was increased. And if you do have a prop strike, which is IMO an inevitable outcome of high frequency instruction, it is a lot less expensive with a fixed pitch prop.

IMO, Decathlons are almost TOO directionally stable on the runway. You don't master the tap dance like a Citabria or Champ demands of you. And that Decathlon really wants to nose over and dig that $10,000 prop and $30,000 engine into the pavement.
 
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100% with Ed here. I think tailwheel, upset training, and demonstration / introduction to acro are best with a Citabria, and acro training is by far best with the Super D. Bart - VanSant used to have a Super D that they tried to use for both purpose, and they prop striked it twice (once with a ground loop, once with nose over). This soured them on the idea, and they stuck with cubs for tail wheel. I started acro on the Super D - to be honest, I'm not sure I would have got hooked as much on the Citabria, due to the extra work it requires. Sure once you're proficient with acro you work around its shortcomings (fixed pitch, slower rate, non inverted), but in the beginning it's just too overwhelming. Even transitioning from the super D to the Citabria is a learning curve, I definitely pushed my engine into the red a couple times.
 
volvo164 said:
VanSant used to have a Super D that they tried to use for both purpose, and they prop striked it twice (once with a ground loop, once with nose over).
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I got my first tast of aerobatics at W66 in Warrenton VA about 22 years ago. Their Super Decathlon met the same fate. On perfectly smooth level pavement, no less.

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You guys are confusing flying aerobatics with providing a worthwhile teaching experience and the goals of the business owner! If you're new to aerobatics, the performance of the plane is secondary to it being safe and capable of delivering the lesson. A Cessna 152 Aerobat can do that and it isn't a Super Decathlon! A 7KCAB with its aerobatic certification, inverted fuel and oil, and appropriate harnesses and chutes (and a bad ass paint job 🤘🤘🤘) will keep a pilot that is new to aerobatics more than stimulated and will teach maneuvering skills that will carry through a lifetime's worth of aerobatic experiences. And it will be less expensive to operate, more reliable (no constant speed prop or governor, less mechanical complexity equates to more reliable. How long would the plane be down to have the prop overhauled unexpectedly and how much would that cost??), and cheaper to purchase/insure.

If business is so good that you have students coming back to you for contest aerobatics training and they're already beyond Primary, then sure, buy a Super D but the potential to bring traffic through the door has to justify the investment.

The back and forth with you guys is fun, you made some good points but I'm still in the camp that the 7KCAB isn't getting its due respect!
 
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Oh, memories of Van Sant! Way back when, one could solo their Stearman. I think I flew it solo twice. The second time I taxied in or out right behind the "Cannibal Queen" which had just recently been sold by Stephen Coonts. The following week I called to reserve the Stearman and somebody had busted it.....the end of a good thing.
 

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@DanO, I moved from Northeast NJ about sixteen years ago and had never even heard of Van Sant! I had no idea it was there and here we were, we had just moved to within twenty minutes of the place! Got checked out in the Cub, then the Super Decathlon. Never got around to the Stearman although the current owner of the business has a Stearman available again. What a place!
 
Bob Turner said:
Did you know my buddy Orton Ogborn at Van Sant? Spent many happy days as his F/O in a Nord.
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No I did not - I only knew some of the some of the FBO / instructor folk (who changed over the years) as I would fly in for tailwheel and some aerobatic training many years ago.
 
Didn't expect, but not surprised, of so many people loving Van Sant: so why don't we do a meet up there in '22?
 
Bartman said:
You guys are confusing flying aerobatics with providing a worthwhile teaching experience and the goals of the business owner! If you're new to aerobatics, the performance of the plane is secondary to it being safe and capable of delivering the lesson.
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There are a few business owners who have built successful aerobatic instruction operations with the Decathlon as their primary trainer. Patty Wagstaff, Greg Koontz, Michael Lentz/UND, Adam Cope. You might have heard of some of them. ;)
 
ja, it's good work if you can get it!

But until people are listing you by name on the internet, maybe the budget is tighter and the airplane has to do more than loops and rolls! I stand by my assertion the 7KCAB is a blue collar instructor's best bet and that it's better than even we realize. In fact, I'm wondering why ACA doesn't push it more as the overall best choice for a flight school that wants to do tailwheel check-outs, CFI prep spin courses, and intro to aerobatics coursework. It's like three curricula being added to your school in one airframe and it couldn't be any easier to maintain and operate.

The 7ECA, or Aurora as it is known today, is the perfect tailwheel solo rental. Sure, people rent Cubs all the time but a 7ECA has a transponder and a battery/starter so I'd have to guess insurance companies would smile at that.
 
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Just like buying a plane : define your school's primary mission, and get the plane for that.
  • 7ECA is perfect for tail wheel - can do upset recovery, and intro to acro
  • Cessna Aerobat - perfect for upset recovery (feels more like other GA aircraft) and can do intro to acro - can also be tied down outside, which is often a big plus for commercial ops
  • Super D - perfect for acro, can do tail wheel, and upset recovery, but costs a bit / fair more
Before getting my 7ECA, I was in final negotiations on a 150 Aerobat tail wheel - but researching the STC found that it's not legal for intentional spins. The seller, who was using it for introductory acro training, simply said it spins fine (which I believed him), and who's to say that in a lesson the spin was intentional or not. Since I always wanted to try a competition, I knew that wouldn't fly.
I would agree with you that the Citabria is a great all around choice. But heck getting a Cessna 140 and 150 Aerobat will not cost you much more than a 7GCAA, together probably insure for barely more than a GCAA, and 2 tie downs cost you less in terms of storage. 140's are used quite a bit still for tail wheel check outs.
 
Bartman said:
I'm wondering why ACA doesn't push it more as the overall best choice for a flight school
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Well I think the short answer to that question is that there are not very many of them, and the ones in the field are all very old, while the Decathlon is still in production. I have never even SEEN one.
 
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