Aerobatics in the 7ECA

Sportsman was originally supposed to be flyable without inverted systems. The category was established in 1970, while the Decathlon was not produced until 1972. However, IMO category creep away from that intent has been a problem over the years.

The people who submit proposed knowns are experienced high level competitors. They are trying to come up with something "new" to keep long-time competitors returning. Rather than sticking with "boring" standard figures, they try to jazz them up. Thus we get figures like sharks teeth, humpty bumps, and vertical rolls, which were not present in sportsman when I was competing 15-20 years ago.

It's all well and good to challenge people, but those maneuvers significantly raise the barrier to entry for new competitors. They also make it much more difficult to complete the sequence unbroken with a low power aircraft such as a Citabria. My personal view is that anyone who thinks Sportsman is not challenging enough should be in Intermediate.

I plan to compete in 2021. It will be interesting to see and discuss the known when it comes out.
 
Well, based on feedback here and after watching the replay (i.e. my instructor's video of my 1st acro flight in the 7ECA) and the dismal roll rate, I decided to bite the bullet and order spades from ACA.
 
Ed - plus 1. No vertical rolls for me! Three classes should be plenty, with no requirement for an inverted system in the lowest class. I really have no say in the matter; have not competed since 1976.
 
Big Ed said:
Sportsman was originally supposed to be flyable without inverted systems. The category was established in 1970, while the Decathlon was not produced until 1972. However, IMO category creep away from that intent has been a problem over the years.

The people who submit proposed knowns are experienced high level competitors. They are trying to come up with something "new" to keep long-time competitors returning. Rather than sticking with "boring" standard figures, they try to jazz them up. Thus we get figures like sharks teeth, humpty bumps, and vertical rolls, which were not present in sportsman when I was competing 15-20 years ago.

It's all well and good to challenge people, but those maneuvers significantly raise the barrier to entry for new competitors. They also make it much more difficult to complete the sequence unbroken with a low power aircraft such as a Citabria. My personal view is that anyone who thinks Sportsman is not challenging enough should be in Intermediate.

I plan to compete in 2021. It will be interesting to see and discuss the known when it comes out.
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woo hoo! in which category?
 
there were a couple for sale, maybe 5 yrs old, about $1600 each I think. either Barnstormers or Facebook. are you on the acro email list?

go to this page, scroll down to where it says Sign Up and then follow the directions. anybody can join

Aerobatic E-mail Distributor

acro.aerobaticsweb.org acro.aerobaticsweb.org
 
I've been on the acro exploder for about 20 years, but had long ago stopped reading the emails. Thanks for reminding me. Now that Guenther moved it to Google Groups, I can go there and search.
 
Anyone have issues with their carbs after acro? As I was practicing hammerheads with the instructor, we snapped / tumbled hard (sideways twice, and backwards once). I realize that I waited too long to kick the rudder - but the issue is that the engine started running rough, especially at lower rpms (2200 and below), afterwards. On the ground, I noticed that the idle RPM dropped from 800 to 500, and I needed to really lean to get it to run well. Plugs are carbon fouled - but mag check showed no anomaly. I can see the blue stain around the carb - so she's definitely running really rich. At cruise power, it seems OK. The signs point to the idle circuit needing adjustment - but why would it change so drastically after an aerobatics session? Could the carb float have been damaged by the tumbles?
 
Dunno about the carb, but you shouldn't be snapping out of hammers so easy.
What cue are you using to time the rudder kick? What is the sequence of your control inputs?
 
Big Ed said:
Dunno about the carb, but you shouldn't be snapping out of hammers so easy.
What cue are you using to time the rudder kick? What is the sequence of your control inputs?
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Well we were trying to see the fabric under the wing start to vibrate, also tied a string on the strug. Didn't work. I was then informed by my previous Super D instructor to pay attention to the back of the plane, and as soon as the prop wash starts to bang on the sides in the back, kick the rudder. I now remember this working in his Super D - I'll have to see next time if the 115HP does the same. Control input was full left rudder, then right aileron, then right aileron forward stick. Next time I'll pre-load rudder to the right as it's slowing, allowing for a stronger left kick. Once it snapped over, it also wanted to fall over onto its back, either it was too much forward stick, or the flat bottomed wing wants to pull it onto its back.
 
I was taught like your previous Super D instructor. Kick when you feel the slipstream vibrating the fuselage. Very distinct sensation. Should have plenty of rudder authority because it catches the slipstream. Can't speak to the lower HP aircraft though.
 
volvo164 said:
Anyone have issues with their carbs after acro? As I was practicing hammerheads with the instructor, we snapped / tumbled hard (sideways twice, and backwards once). I realize that I waited too long to kick the rudder - but the issue is that the engine started running rough, especially at lower rpms (2200 and below), afterwards. On the ground, I noticed that the idle RPM dropped from 800 to 500, and I needed to really lean to get it to run well. Plugs are carbon fouled - but mag check showed no anomaly. I can see the blue stain around the carb - so she's definitely running really rich. At cruise power, it seems OK. The signs point to the idle circuit needing adjustment - but why would it change so drastically after an aerobatics session? Could the carb float have been damaged by the tumbles?
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just curious, do you recall if the controls were neutral when it was falling out of the botched hammerhead or were you trying to recover through all of that?

I was thinking the carb float got jostled, is it fixed or still rich?
 
Bartman said:
just curious, do you recall if the controls were neutral when it was falling out of the botched hammerhead or were you trying to recover through all of that?

I was thinking the carb float got jostled, is it fixed or still rich?
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Controls were not neutral - when we snapped side ways, I was following through the left rudder, then right aileron, then forward stick. It more or less did what it was supposed to, but instead of graceful turn, it snapped around with big pendulum swings side ways and forward tumble past vertical, correcting both with rudder and pulling back on stick to straighten out. These weren't too bad, but the one where snapped backwards - done by the instructor - is where snapped hardest with my mounted portable GPS falling off due to a strong negative G jolt. Not sure about control inputs here - but felt like an even later entry, and I'm guessing delayed stick forward.
Installed a new (rebuilt) carb yesterday, now running smooth. We didn't take the old carb apart - with a $600 core charge I figured let's now mess with it. Carb was quite old. We (mechanic and I) suspect the float got damaged.
 
What I meant to ask was if you were trying to undo the botched snap as it was happening or did you neutralize the controls and let it just fall out of it?
 
Bartman said:
What I meant to ask was if you were trying to undo the botched snap as it was happening or did you neutralize the controls and let it just fall out of it?
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Oh right - well, I don't remember to be honest, it happened quick, and afterwards I was trying to stabilize a straight down vertical diven, before pulling out. But I think I held control input steady, and firmly, given the instructions to make sure to not let controls jump out of my hands, in an inadvertent tail slide.
 
Welp, one thing is for certain: you either had too much airspeed, or too little. 😁

If you kicked too early, the forward stick may have caused a snap roll. You would have to kick really early though.

If you kick too late, you probably got into an incipient tailslide or gyroscopic maneuver. Impossible to predict what results the control inputs will produce, since you cannot reliably predict airflow in that state. Eventually it will fall out. Centering your stick is usually best when that happens.

Focus on the vibration in your tail, kick as soon as you feel it, and all will come together.
 
I'm not home so I can't read the acro placard for speeds but let's say you enter at 130 with a 115 hp Citabria, about how many seconds do you have before the kick for the hammerhead? just curious, thanks.
 
Entry speed is 145mph - you actually get quite a decent vertical up line, it's really more momentum than HP I think. I think the issue is towards the top, with the lower HP producing less torque, thurst, plus the carb fed engine starting to stutter, the plane simply runs out of upward momentum more suddenly than how I remember it in the Super D. As was pointed out, the kick should be timed so that the vertical speed is 0 at the top of the turn, not the start of the turn. We definitely kicked late.
 
Today I finally had the opportunity to do solo acro in the 7ECA - about a month after my last lesson. Quite nervous, but the maneuvers went great. Big difference 1 up that's for sure, everything was easier (although I stayed away from that hammer head). Rolls were easier, but as this was my first solo outing, I only did slow rolls, loops, humpties, and a spin. My spades arrived a while ago, they'll be getting painted and installed next week, then I'll tackle the cubans and immelmans. Will also start putting the sportsmans sequence together. Also starting to establish a system for throttle management. On most of the previous flights, I would red line more than a few times :-0 What kept getting me was the how much the prop would speed up at right at the end of either the initial dive to speed, or the pull out. Also, putting power in too quick on the pull up. My current approach is:
- Set 2400 for slow roll (dive to 120), leave it for the duration of the roll
- Set 2400 for loop (dive to 140), leave it till top of the loop, then pull back to about 2000 or 2200
- Set 2300 for humpty (or hammer head) dive to 145, pull to vertical, then add full power
I'm not yet concentrating on the energy or the next maneuver, may adjust my power coming down from inverted / vertical maneuvers accordingly ( to hit entry speeds for next maneuver) Anyone has a more refined system for power management for fixed pitch?
 
I'm spoiled, have never flown acro with fixed pitch. Worrying about RPM would stress me out. One day I would love to get a Pitts S1S, so I maybe I'll learn then.

@volvo164 Where did you get the spades?
 
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