Sportsman 2021 Known

Big Ed

Big Ed

N50247 - '79 Super D
Joined
Jul 20, 2020
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Tampa, FL
Read on Acro Group that the IAC approved 2021 known proposals. I was curious what Sportsman would look like, since I hope to compete this year. A few critiques from someone who has not flown in a long time:

1. I personally feel sharks teeth and humpty bumps are unnecessary and counter-productive for Sportsman. First, newer pilots will have to learn to fly those more advanced maneuvers instead of perfecting finer points of more fundamental maneuvers. Second, less powerful aircraft are disadvantaged. While the stated target aircraft for Sportsman is the Decathlon, in reality this sequence favors Pitts drivers who should be moving up to Intermediate.

2. Are wind correction maneuvers not a thing anymore? That was the most challenging decision making skill to acquire during Sportsman. I felt it was good to learn early, but looks like they slid it to Intermediate.

3. How much imagination would it have taken to turn one of those 3 cubans into a reverse cuban? Roll to inverted on 45 upline takes some practice to master rudder inputs. If you do it sloppy, you find out when you pull through off heading. That's what I mean by finer points of more fundamental maneuvers.

4. No spin? A 3/4 or 1 1/4 spin makes a natural WCM. Wonder if this was a nod to the RV crowd. Those have always had a reputation as terrifying to spin.

Overall, it looks reasonable, and I am looking forward to learning it. Gotta get a chute first. That is turning out to be a bigger challenge than I expected.


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Wonder why they took out the spin. Haven't learned shark's tooth yet - I assume it's a combination of a humty and 1/2 cuban. I had no issues with the verticals in my 7ECA, just don't make the verticals long. Actually found the humpty to be the most fun maneuver yet, as it makes loops more exciting. I also enjoy the aerobatic spins - really surprising it's out. Did they remove it from Primary as well? My aerobatics instructor (from Nashua NH) has said he couldn't recall seeing an RV at a competition. The funny thing is that I passed on a tail dragger Aerobat prior to getting my 7ECA, because the tail conversion didn't allow it to do intentional spins, and I wanted to try competitions.
They also took out the split S, and like the sequence of hammer to slow roll to competition turn, should be easier with low power aircraft like the 7ECA ...
 
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Finally ready to start practicing this sequence. Sebring contest is in 2 months.

I really need a sight gauge. Just not able to set 45 lines with any degree of precision without it, especially inverted. And there are a lot of 45 degree lines in this sequence.

I started working on the humpty. Basic maneuver is simple, but flying a non-ugly one is not so simple. Anyone have advice on timing cues for the pull over the top

I did something I have never done before: held a hammerhead too long and started into a tail slide. For just a moment that plane had a mind of it's own.
 
Hello all, Looks like this thread has some time between postings but here goes.

I just competed in my first IAC competition in my 7ECA at the Ohio Aerobatic Open. I came in second in Primary......out of 2. But hey, still second. It was a great learning experience and found out I have a lot to learn. The advice I got was to "go faster and pull harder". When I fly acro for fun, I dont pull level when I start my loops etc since pulling level bleeds off so much speed in the ECA so you have to go faster to allow that momentary level off for competition. Makes things interesting

So my question for the group is.....does anyone flying the primary and sportsman sequences with non-inverted equipped planes, let the engine quit in order to fly the inverted down lines? I know oil is still pumping with the prop turning but just feels like it could be hard on the engine. I don't mind the moment of silence but if it is shortening engine life, I will avoid it. I know I will lose points buy not establishing the inverted downline on cubans or a top line on an immelman if you don't go negative and a shark tooth is really not possible if you keep the engine running.

Seems there should be an allowance for flying within the limitations of the aircraft and making things look as good as you can without going negative.
 
I'm still working on my maneuvers - in particular the 1/2 cuban. I've been reluctant to extend the inverted downline - so I usually set (or try to set) 45 inverted, push to feel negative G for like 2 seconds, and start the roll. Engine won't quit (but starts to cough in the roll). Suspect this won't do for judges. Also, for non symmetrical wings - the down line angle shouldn't be 45 degrees on the horizon in order to actually have the plane descend on a 45. I was figuring that since I'm only holding the downline for 2 seconds, the angle of the plane would be more visible than the descend path, so I've been aiming for the 45 view on the horizon. Haven't tried the shark tooth yet - is the issue that given the slower speed over the top, one must extend the inverted downline to build up speed before the roll - and hence resulting in engine quitting?
The other challenge I'm having is losing quite a bit of altitude through the routine. I'm more worried about red lining the engine than having it quit momentarily. Given the low HP of the 7ECA and fixed pitch prop, it's a PITA to manage RPMs to maximize your altitude. I've been conservative about keeping power in / putting power back in on the descents, so with power reduced, I'm losing at least a 100' - but probably more - after each maneuver, in order to hit the entry speed for the next one.
My aim is to be happy with myself doing primary then sportsman routine to the best of my and my plane's ability.
 
Congrats! The learning point of the first contest is mostly to learn how to participate in a contest. So ... SUCCESS!!

Honestly, I don't think you can be competitive in the current Sportsman sequence without inverted systems. You are just going to have to make too many compromises. That doesn't mean you can't compete, but you probably are going to have to be content with a moral victory.

Having said that, Adam Cope is the IAC official sequence check pilot. He flies every Sportsman sequence in a Citabria to confirm it can be done. If you are serious about competing in a 7 series, I would look him up on the acro group and see if he has any tips.

If you really catch the bug, you will probably want to upgrade to a 7KCAB or 8KCAB so you can set those inverted lines without turning off the pilot's fan.
 
@volvo164 Sounds like we have similar experiences. As for the fixed pitch issue, I recently installed a Electronics International tach that flashes yellow at 2700 and then red at 2800 so it is a bit of help as I can catch the colors out of the corner of my eye.. I wish there was an audible signal indicating redline but I have been pretty good at managing the rpm. On the humpty, it would have to be a brief vertical up line and then pull and you could keep some speed for the roll similar to the half cuban. I dont think there is a requirement for a long up line in the humpty. Just establish the vertical and then pull and the result should be the same as the cuban.

The Shark tooth is another story. Again, I think it would have to be a short up line and hard pull at the top with no float to keep some speed for the roll.

As for altitude loss, I lose about 1500' total in the primary sequence after I finish the 45 up and end up at 2000' AGL I use the spin exit to get to 150+ so that I can pull level and still have 145 for the cuban but that chews up vertical real estate.
 
@Big Ed. I agree with you on the compromise and that is OK with me. I used to own a Super D and that was great fun but the 7ECA is my retirement airplane and I want to learn to fly it to the best of its and my ability. I am trying to avoid the bug costing me more money. I don't mind the compromises but it sure is hard to do a slow roll after a 180 deg turn without significant pitch up.

Do other people let the engine quit upside down and do you know if that is bad for engine life?
 
If you are losing too much altitude, I would start by looking at the shape of your figures. Are you getting enough float over the top, or are you squashing the top of your loops?
 
Yup....deductions for pinched loops and cubans but that keeps the engine running. I use the down line on the cuban and spin to get energy back and I cheat the down side of the loop a bit to get more speed into the turn so that is where my altitude goes. STill have a lot to learn.

One thing I did learn was that you fly each maneuver by itself and forget about what you just did or what you are going to do next. The advice I got was to "expand my mind" ....without any mushrooms of course.
 
Ed - I'm obviously not an expert acro pilot yet - but I feel it's the low HP and fixed pitch that's costing us altitude with the 7ECA. Keep in mind that full power gets us about 105mph level - and it takes quite a while to accelerate to that - putting us outside the box. Everything needs a significant dive. This - along with the fixed prop where we can't keep thrust going optimally around the maneuver - results in the need to keep diving at the pull out end of maneuvers. Even with a nice float on top for a loop, the natural tendency for the plane, with proportional Gs to pull up, will be to finish at around 110-120mph - and indeed level with the start of the maneuver, hitting your wake turbulence - but obviously this isn't enough for the 140 - 145 needed for the next maneuver, so the pullout, downlines, etc., need to be extended to get that dive in. When I flew the super D - this is just not an issue - a proper nice round loop lines you for the next one. I suspect even the GCAA will be much better in this respect. This is why I was trying to keep as much power in as possible on the descend - but this resulted in redlining a number of times (especially in the 1/2 cuban) - so I'm giving up so that I can just concentrate on getting the maneuver right.

Yeah - and as loopnroll said - we'll end up with 100mph at the end of the primary, at best, doing an ugly looking slow roll with significant pitch up.
 
volvo164 said:
I feel it's the low HP and fixed pitch that's costing us altitude with the 7ECA.
Click to expand...

That is unquestionably the case. My point is that since you are already at an energy disadvantage because of HP and prop, you don't want to waste the energy you do have. You want to fly your maneuvers in a way that maximizes energy retention and avoid situations where you must come off power.

I'm no expert, having never flown fixed pitch, so I'm speculating here. I think you want to milk as much vertical as you can get in the Cubans, so that you start your diagonal at a very low airspeed. That gives you more time to complete the roll and pull out before hitting redline, so you can keep power in.

One thing I do know is that our planes are larger than most competing aircraft, which means they look lower in the box. I was told that judges will usually give sportsman pilots the benefit of the doubt at the top of the box, but not the floor. So, a good strategy would be to start as high and fast as you can to maximize your kinetic energy. If your loops gain 700 feet, I would climb high and dive into the box at 3000 AGL and close to redline.

Of course all of that was pre-ADS-B!!! Not sure how it works now that your aircraft can tattle on you.
 
@volvo164 Your description is exactly my experience. We are getting as much out of the plane as we can. I have a piece of tape on the side of the throttle that tells me where I am at on downlines so I go full at about the time I get vertical for Cubans, Wingovers, loops etc and then leave that there till I start accelerating down hill. Then I pull back to the tape spot and that will let me get back to 145-150 without going over redline and without staring at the tach.

Question to you other 7ECA/GCAA pilots: Do you let the engine quit inverted or take the deductions for pitch up and short down lines before rolls.
 
I don't think letting it quit is an issue for the engine - the amount of time upside down, running low on lubricant is the issue. I forgot what the manual stated - but it's something like a minute that we can run upside down: of course the only way to do a minute would be to glide upside down for quite a while, but just because the manual says so, it doesn't mean it's good for the engine. Regardless, what your oil pressure gauge says, the engine will not be plumbing oil to the cylinder heads while it's in negative G. I'm running straight weight 100 oil with the hope of thicker viscosity helping to retain lubrication. By the way redline isn't that much of an issue for the engine - as it is for the prop. Lycoming specifies the amount time redline can be exceeded (again bad with remembering numbers) but we've got thin noodles for props on the 7ECAs and they'll bend if pushed too far.
The tape on the throttle quadrant is a great idea
 
A minute is a really long time for no oil pressure. When mine goes to zero it is five seconds, and even then I feel uneasy.

That minute may refer to the inverted fuel system. Mine is limited to two minutes, and when you exceved that it really lets you know.
 
As long as there is no sustained inverted elements the most time you would have to spend upside down would be 2 seconds for the down line prior to roll. Shark tooth, Cuban, reverse Cuban only demand -1 before the roll so the question is, does 2 seconds of silence hurt the engine. That is of course every time you practice those maneuvers. Not sure how loss of thrust affects the maneuver.
 
I indeed made a mistake about the manual - the 2 mins was for the 7KCAB. :slap:
So I've been trying to search the web on this - and can only find people commenting that momentary loss of oil pressure is not an issue at all. But I couldn't get a definition of what momentary is. Whether the engine is firing or not shouldn't make a difference, if anything if the engine quit - it's not producing heat in the cylinder head. I started to think about power - in the slow roll, we have power in, but the inverted section really is momentary with the engine coughing a bit. In the cuban power is in but pulled back - and I now wonder if being conservative with RPM is beneficial for the engine. I've only lost power in the Cuban and Immelman. I've not lost power sow far in the hammerhead - guess my upline isn't truly vertical LOL - but even the books on the subject suggest keeping a slight positive G for non-inverted oil system planes. In the automotive world - an engine will run roughly 15 mins without oil before seizing - but damage would start to occur much earlier - but still in minutes. I don't think we'll ever exceed 5 seconds in negative or 0 G - engine running or not - and this probably isn't any worse than an engine start - and probably less harmful than engine start on a cool day.
 
One way of looking at it is that aerobatics are hard on any engine. Most aircraft used primarily for competitive acro get less than 1000 hours TBO.

So from that perspective, the momentary loss of oil pressure may not be significant compared to the abnormal wear from hard maneuvering and redlining your RPM.

Any opinions you get are going to be speculation and anecdotes anyways. Nobody really knows, unless someone has done a scientific test where they tested engine life expectancy under those conditions and compared to a control group.

Bottom line, if you want to fly competitive acro, you have already decided not to baby your engine or your aircraft. So do what you gotta do, and try to keep the inverted periods down to the minimum necessary to fly the maneuver correctly, 1-2 seconds max. Worst case, you wear out your rings and get to TBO faster.

I did notice a couple of 7KCABs listed for sale recently. That's basically a 7ECA with inverted systems, so if you are really worried about it ....
 
I'm going to wait until the FAA announces revisions to light sport next year : it's expected that a much higher gross weight will be allowed via some sort of formula taking hp / wing loading into consideration. I would expect the 7 series to become light sport eligible, but not sure beyond that : complex prop, retract, 4 seats, etc. Regardless the 7ECA is just so neat for its simplicity, useful load, fuel economy / range, and ability to still be dragged through the sportsman routine!
 
Continuing to practice the individual maneuvers. I plan to fly every day this week and next. By late next week I hope to put the sequence together and bring it down to target altitude.

I was losing a lot of altitude on Cubans today. Finally figured out the second half of my 45 was too steep because I was not putting in enough top rudder on the knife edge. Fixing that helped quite a bit with airspeed on recovery.

The other helpful thing is focusing on getting full aileron deflection on the half roll. It's really easy to inadvertently relax when the stick forces get high. Consciously pushing to the stops gets an improved roll rate.

Flew the sharks tooth today. It is pretty easy. Probably easier than the humpty because you don't have to worry about the radius speeding up at the end.
 
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