MI Aerobatic Open was great!

Great weekend, great contestants, great weather - it all came together.  24 contestants flew three flights each, and we had at least three contestants in all categories.  21 aircraft participated. We had six first-time competitors, including a guy who flew intermediate at his first contest!

Not that a whole bunch of people didn't jump in and rescue things many times - there was much I didn't know either how to do or even understood that it was needed in the first place. Our chapter is blessed with some very, very experienced and capable contest help. But we also brought a few new things to the party and it really made a difference.  When I have a little more time I'll write more about:

1)  Public relations and what it can do for the event
2)  The stuff that isn't in the Contest Director guidelines, as complete as they may be

For now I'm off to catch up on other work.  One future event for me is giving the September IAC webinar on the aerodynamics of basic aerobatics - Part 1.  We can't do it all in an hour but I'll get us started on that one.  Stay tuned for the date and time and signup details. - Don

Air Traffic Controller's Blog - Recommended Reading

Very interesting, very good reading - the blog of DeltaMike, ATC guy in the Boston ARTCC.

Botched Maneuvers - How Bad Can I Screw Up?

Acro Camp Sneak Peek 01 - The Hammer-Spin from Steve Tupper on Vimeo.
Jim discovered that the Pitts will make a nice inverted spin entry if the stick is held too far forward during a pivot on a hammerhead.  The Super D Jim flew previously has a metal prop and needed some forward stick on the pivot to overcome gyroscopic tendencies for the nose to pitch up, but the Pitts has the MT prop and little in the way of gyroscopic force - the same forward stick shoved it right into the inverted spin.  The problem was that Jim didn't see it for what it was at first and held it in the spin instead of letting it go - hey, if there's ground in the window I should push to break the stall, right?  Well, not in an inverted spin!

Time for a short summary of just how badly one might screw up a maneuver.  This is the unknown, the terror factor, the pucker, the thing that scares many out of trying aerobatics...we could bend the plane or worse!  What if we can't get out of it, whatever IT might be?  Well, we have a saying in acro - don't run out of altitude, airspeed and ideas simultaneously - and since we keep that altitude buffer healthy we have lots of time for airspeed and ideas.

Good news.  Botched maneuvers come in three flavors only.  That's it.  And the plane can be safely flown out of every one of these situations.  It just takes training.

Flavor 1.  Unintentional Spins

Flavor 2.  High speed excursions

Flavor 3.  Unintentional tailslides.

There's a place that a new aerobatics pilot reaches somewhere around the mastery of Sportsman maneuvers and botched maneuver recovery training where it dawns on them that they don't really care where they end up anymore.  I don't mean that they aren't trying to fly well.  I mean that if the maneuver doesn't work out they aren't worried about it at all.  They'll just laugh it off and try again, because they really know that whatever happens (pick your flavor above) they can fly out of it just fine.

My first really good I-can't-tell-what-is-happening botched maneuver was an unintentional outside snap (just an inverted spin really) from an outside half-loop, starting inverted and pushing to level upright.  At about 30 degrees nose up on the top side, looking out at the horizon to my left because there wasn't anything over the nose yet, I pushed too hard and got an inverted snap roll.  Being how I was looking left and not forward at the break I just remember an illogical sequence of Galveston Bay, sky and the Texas City coastline off to one side flashing momentarily into view and disappearing, all the while listening to my instructor laughing in the back seat and saying "ha, you really botched that one!"  And I was quite pleased to discover that I wasn't scared.  Close the throttle; let go, watch over the nose and try to pick off the yaw...before I could even get on a rudder pedal the plane fell out of the snap and I pulled it back level...and we tried it again with a successful outcome to the half loop on the second try.  But it had happened - a spin that I had not intentionally set up and to this day I don't know which way it was going around.

So here's the short version of botched maneuver recovery:

Unintentional spins.  Good news - while you might be getting dizzy, the aircraft could care less.  It isn't going very fast as the spin is preventing much in the way of any increase in speed.  You won't bend anything while you are spinning as long as you avoid hitting the ground before recovery.

Biggs-Muller to the rescue.  See this Dick Bevington article for more.  Close the throttle, let go of the stick and apply opposite rudder.  P.S. If it isn't clear which rudder to press (can't tell the yaw from the roll - they are opposite in an inverted spin) then press one rudder pedal all the way to the floor.  If the plane doesn't stop rotating nearly immediately then press the other rudder pedal!  The correct pedal to push will be the harder one to push.  The spin will stop nearly immediately; grab the stick and recover to level.   Works for any type of spin in the Pitts and most others. For Decathlons - when you let go watch out for the stick to float into a corner and stay there, especially for inverted spins...push the stick back a little toward neutral with an OPEN hand (don't grab it, just nudge it toward zero aileron and nearly neutral elevator) and the stick will suddenly take on a life of its own, pop into a neutral position and the spin will stop.  See the POH for comments on that one - I've seen it happen and used the technique a number of times.

High Speed Excursions.  This one usually won't get you dizzy because you are just diving something silly, upright or inverted, and we really can bend something if we don't do something about it properly.  Remember, getting rough with it way above maneuvering speed is an issue.  The trick is to load the airframe properly.  Pulling g's cranks up the induced drag and stops the speed excursion in its tracks.  So: 1) close the throttle, 2) roll blue side up (without pulling!) and 3) pull about 4 g's to level to stop the acceleration.  I see this most often early on in the half Cuban.  A student will take too long fishing around looking for the 45 downline, all the while accelerating at full power in the inverted dive.  It doesn't take long to get uncomfortably close to redline.  Pulling the throttle to idle slows the acceleration remarkably.  Rolling without pulling will avoid over-stressing the wing with the higher angle of attack in the roll.  Then a straight back 3 to 5 g pull will stop the acceleration completely.  Using this technique I can take a straight down vertical, 140 mph full power dive and have the plane level at 160 mph.  The mistake most make early on is pulling during the roll and/or not pulling hard enough after the roll upright is completed.

Unintentional Tailslides.  This is more of an issue in aircraft that aren't approved for tailslides (like the Decathlon) but we treat them the same in all aircraft.  If the nose is pointed way up and the speed is almost gone, it is much easier and cleaner to yaw out than pitch out.  The idea is to do something like a hammerhead - not a humpty.  I've seen unintentional tailslides in the Decathlon when a student pushed too hard on the roll in a half reverse Cuban, loosing sight of the horizon; I'm watching us push up to a vertical attitude out the side while the student is looking for the long-gone horizon high in the window and wondering what happened to it. If the situation isn't recognized until it is too late to avoid it 1) pick a rudder (hopefully toward the low wing if there is one) and stand on it; 2) hold the stick really tight and usually a little forward (to make the plane flop over on it's back if it doesn't yaw out first - that seems more comfortable for most pilots to handle) and 3) close the throttle if it doesn't yaw out right away, but do close it as the nose swings down.  Be prepared for the maneuver to continue into some sort of spin entry and do the usual recovery from that if it happens.  The Pitts will sort of stick in a nose up vertical slip...if the right wing is really low, full left rudder won't make it pivot and full power holds it there - it just slides down sideways.  Eventually it will flip over (with sufficient tailslide speed) but closing the throttle results in an immediate end-swap and recovery.  Hanging on tight to the stick will help prevent the controls from slamming to the stops in the tailslide - and believe me, they will try to get away from you.  I usually grab it with both hands if I think it might happen.

In summary, there's no situation which will result in bending the aircraft if the pilot recognizes it and properly recovers.  The key is getting enough training to not lose track of what is going on.  Then the worst of a botched maneuver is a bruised ego.

Contest Registration On-Line (Michigan Aerobatic Open)

Go here to register for the competition!  Game on!  We have sponsors, we have staff, we've got a waiver for the aerobatic box approved.  Airport is on board, as is ATC and the county safety folks.  Hotels arranged.  Gotta plan the Saturday evening banquet food - yum.  We have a speaker - Steve Tupper of Airspeed will speak about military rides, AcroCamp movie and AcroCamp II plans and other fun stuff and might have a few clips to show.  We are off to order shirts and trophies next week.  So far so good - and thank goodness the IAC gives us a big checklist so that we don't forget anything.  Potties.  Gotta order the potties.

Clear Prop Actually Means Something

That's either a really big prop or a really small Pitts.  Actually, it's both.  Hugh flies Unlimited in it (S1E).

We take safety more than seriously at IAC competitions and a student I had yesterday reminded me of a pet peeve - and for what are blogs if not pet peeves?

What good is yelling "CLEAR!" if the prop is turned before there's time for an answer from a surprised individual in front of the aircraft?  What good is saying it if not loud enough that someone in front of the plane would hear it?  Isn't that the point?  I sometimes say "hey, wait!" to a student right after they say "clear!" and guess what - most start the engine anyway because the key was turning even as they shouted out the window.

At IAC competitions we provide a "Starter" person who clears the area and signals the pilot before the plane is started.  If you don't have a Starter person, I strongly suggest waiting a few seconds to see if a surprised voice says anything from out under the cowl before turning the key.  If you don't think there's any possibility of that then stop looking stupid and yelling clear.  It obviously doesn't mean anything.

Michigan Aerobatic Open Sponsored by MT-Propeller

Things are rolling right along in preparation for the July competition.  We have our box waiver completed with the FAA and personnel assignments coming along nicely.  Right now we are getting hotel rooms lined up, setting up the on-line contest registration and obtaining sponsors and planning for the coveted contest shirt and trophies.

MT-Propeller has agreed to sponsor the competition by contributing toward those cool shirts and we are very grateful!  I happen to fly a Pitts equipped with  the MT prop and it is great for many reasons, not the least of which is less wear and tear on the engine from gyroscopic forces - we really believe in this propeller.  Not to mention that it kicks butt and has less RPM overshoots than other props I've flown.

We definitely have room for additional sponsors.  If you are interested or have suggestions please comment or email me (see our IAC88 website for the Technical Advisor email address).  We've got contest brochures, sponsor banners, a big spot on the back of the polo shirts, contest flyers, on-line publicity and more that need YOUR business on them!

Flying Inside the Box

What did we do before Google Earth?  Did we have paper charts and maps of stuff like roads and fields and stuff?  Did we have scales to everything when printers and copiers changed the size of everything?  I don't remember.  I have a vague recollection of considerably more work.

Our Jackson box is shown above, parallel to runway 6/24, which puts it perfectly over swampland but makes it a bit of a bugger to fly because it isn't square with all the wonderful section lines here in Michigan.  And runway 14/32 isn't quite orthogonal to it either.  Runway 32 was extended since this photo; the threshold of 14 is now just west of the middle of the box.  It can be hard to keep flight lines parallel to the box edges when not in a position to clearly see 6/24 from the air.

Runway 14/32 is closed during the competition, but 6/24 stays open for business at all times.

Combine Google Earth with a site like Calculate distance, bearing and more between Latitude/Longitude points (and there are many others, but this one did exactly what I needed) and laying out a box is really painless.  The site calculates distance between points specified by Lat/Long, and also gives the bearing between points and extrapolates points from known positions, given distance and bearing.  All the equations and code are explained also for those who need it, but I just used the plug and play features.

This box is exactly where our box was positioned last year, but I wanted to check it and re-plot it.

A competition aerobatic box is 3300' square (which is a smidgen over one square kilometer).  The east corner is positioned so that the box will sit northwest of runway 6/24 and west of the buildings between the runway and I-94 to the north, with at least a 164' buffer zone from edges of the aerobatic box to runway and buildings.

I set the east corner where it was last year.  The Lat/Long was obtained with a Google Earth marker; I projected the 3300' line parallel to the runway to obtain the south corner, defining the "front" of the box (SE edge).  Then adding 90 degrees to the bearing and projecting north and west corners was painless.  The website gives mid-points between lat/longs automatically, so the middle is easy to find.  I simply typed the Lat/Longs into Google Earth markers, took the screen shot into MS-Paint and threw the box lines in.  Nothing very sophisticated but this is all the FAA needs for depiction and is quite accurate.

We'll use a GPS when we place the box markers out in the fields, and the box will be within a few feet of a perfect size.  From the air it looks very nice and square, however cockeyed to the rest of Michigan as we know it.

The box goes to 3500 AGL, or almost exactly 4500 MSL at Jackson.  The lower limit depends on category, and the Unlimited base is only 328' AGL.  Since the box crosses I-94 just a little, there's a small wedge cut out of the north corner over I-94 which might only affect an Unlimited flight where the base is kept at 500' AGL.  The base for Advanced is 800' AGL and higher for other categories, so they are not affected.

We have line judges at the east and south corners, watching the SW and NE edges as well as the front edge along the runway.  The judges sit safely clear of 6/24 on the south side, almost box center and parallel to the front edge of the box.

So this picture will go in with the 7711-2 form, some pilot procedures documentation, and a page or two of IAC standards, and we'll see what the FAA folks need, if anything else, to approved this year's competition box.  It will be nice to have things in place early.