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Old Mar 24, 2014, 06:44 AM
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Mid-airs

Collision on takeoff yesterday between an Xplorer I and an Xplorer II in Madrid at an F5J FAI competition.

Wind coming at an angle to the launch line caused some confusion regarding whether to launch into the wind, or perpendicular to the line. FAI F5J rules say that launch must be "straight forward" which I assume means perpendicular to the launch line, but the tendency of many folks is to launch directly into the wind.

The good thing about ALES as practiced in Europe was that you had a 30 second window to launch. That meant staggered launches and landings with less likelihood of crashes.
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Old Mar 24, 2014, 09:33 AM
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Portola, CA
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It was my Supra that was hit by a Sharon on Saturday in Davis. It tore off my stab and broke the mount. Thanks to Scott Woodward yelling to me "the flaps will work like an elevator when inverted" I would have completely lost the plane.
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Old Mar 24, 2014, 10:02 AM
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Oooooh that's how you did it! GENIUS!
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Old Mar 24, 2014, 10:50 AM
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Good job Scott, that is SOP for stripped off stabs on flapped ships. Seen it happen to guys going too deep in the well on string launches. Has saved many ships.

Marc
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Old Mar 24, 2014, 10:59 AM
Red Merle ALES
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That really is amazing quick thinking and reactions. That will give the brain a good workout.
I was waiting to hear you even got a 50 point landing! ha ha
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Old Mar 24, 2014, 11:12 AM
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When standing at the launch line of an ALES or F5J contest it might be good to speak to the adjacent pilots to see if you can arrange to stagger the launch so you are less likely to interfere with each other. There is a 10 second launch window.

I have not had a launch problem in the past. But we all learn from each other's experience.


Something to think about. If there is a crowded launch line, a windy day or if you have an off wind angle launch it might be worth considering to extend the launch window to 15 seconds or see if pilots would like to launch in A and B waves by every other station.

Something to think about.
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Old Mar 24, 2014, 11:27 AM
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Ed,
Our typical ALES club event has 10-12 man flight groups. At the pilots meeting the request is made for the higher powered planes to launch as soon as possible to clear the space for the slower planes. Using this simple request I don't believe we've had a launch phase midair, certainly not in the first 10 seconds when the likelihood of a collision would be greatest.

The mid-air that Scott had (Supra vs. Sharon) occurred well into the flight, upwind with both planes scratching to try to make time. It was not during launch nor during landing, it just happened. This is the kind of midair that can happen any time, any place, any type of event where more than one plane is in the air at a time.

JT
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Old Mar 24, 2014, 11:48 AM
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JT, thanks for the clarification. Yes, that kind of mid-air can happen anytime in any thermal soaring format. I have seen planes bump when there were only two in the sky but they were both working the same thermal.

For some reason I thought it was on launch.
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Old Mar 25, 2014, 10:16 AM
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Here is a video short from the 2012 Polecat ALES. About halfway in, you can see Don Harban's Supra get mid aired at launch and resulting inverted crash.

Bit of planning and communication between pilots can cut out most problems. Find you space.

Enjoy!

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ALES Contest 1.mp4 (10 min 30 sec)
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Old Mar 25, 2014, 01:53 PM
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This mid-air kept me up several nights. The plane was fairly powerful and the collision occurred immediately upon launch disabling the stab and putting the plane into a large loop and ending up in a high speed crash that pretty much split the difference between two other pilots. But for the grace of God it could have been VERY bad.

It happened faster than my brain was able to process. My first instinct was to simply try to get control of the plane -- something that was not going to happen in the two or three seconds it took the plane to crash.

After visiting with some better pilots I have added a step to my pre-launch mental preparation which includes thinking through what I would do if I lost control of a plane under power. While my first (competitive) instinct used to be to "save" the flight, it has now become to simply abort the launch (kill the power) if ANYTHING goes wrong during the launch.

There is a big difference between the generic collisions that we see from time to time and a collision that occurs between two planes under power AND in close proximity to other pilots and timers.

At least with the ALES 10 second launch window, it is possible to coordinate your launch with your neighbors' launches IF there is a general understanding as to the planned INITIAL direction of the launch.

Remember -- the real damage on a launch collision might not be to the planes, but to other people.

Happy Landings,

Don
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Old Mar 27, 2014, 12:55 PM
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I've had one midair on launch during my first ALES contest when I walked my Radian up the back of another Radian. Lots of little chunks of foam flew off but both of us finished out the round. Since then I have had no problems finding clear airspace during launches even with as many as 12-13 gliders in the flight group. Landings when everyone maxes are a little more hectic for me with some pilots ignoring the rules about cutting across the lanes or circling on final.

I think most midairs occur in crowded thermal gaggles.

Steve
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Old Mar 29, 2014, 08:46 PM
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Quote:
Originally Posted by dreisinger View Post
I have experienced 3 that I can recall. One was rather scary because the pilot and I really didn't have time to get out of the way. Fortunately, his disabled plane passed by us and crashed behind us. It went in at full throttle. I was flying for the other two and the other planes were going in the same direction as I so we tangled gently and then disengaged. It's bound to happen from time to time. Usually most of the close calls I've seen are at launch. It still should not discourage anyone from competing, just something that happens. It is, at least in my limited experience, rare.

Dave R.
I remember one of those gentle tangles well, because it was with me.
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Old Mar 30, 2014, 06:17 AM
turn, turn, turn.
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Quote:
Originally Posted by dharban View Post
This mid-air kept me up several nights. The plane was fairly powerful and the collision occurred immediately upon launch disabling the stab and putting the plane into a large loop and ending up in a high speed crash that pretty much split the difference between two other pilots. But for the grace of God it could have been VERY bad.

..........
Happy Landings,

Don
I just watched Paul Naton's video again, and saw that mid air...wow!

I pity the fool that bought that crashed hunk of junk plane.

I do understand however, that the replacement wing is suitable for winch launch...so I expect a glider fuse is in my future.
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Old Mar 30, 2014, 06:21 PM
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Originally Posted by smoothvirus View Post
I remember one of those gentle tangles well, because it was with me.
Yeah, Cyrus, at the DESS last year. So sorry you guys had such rotten weather this year. I hope you can make the LISF contest. If not, I'll see you at the Polecat.

Dave R.
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Old Mar 30, 2014, 06:24 PM
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Originally Posted by dreisinger View Post
Yeah, Cyrus, at the DESS last year. So sorry you guys had such rotten weather this year. I hope you can make the LISF contest. If not, I'll see you at the Polecat.

Dave R.
I actually had a lot of fun on Saturday even though it was miserably sloggy and wet - one of the highlights of my day was putting on dry socks after I got back to my hotel room!

Already signed up for Polecat this year.
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