Results 1 to 9 of 9

Thread: Runaway Aircraft. . . .

  1. #1
    not real name 100 Club
    Join Date
    Jan 2007
    Location
    Otherton Airfield, Staffordshire
    Posts
    367

    Runaway Aircraft. . . .

    Heard a story a couple of weeks ago about a bloke who was having trouble starting a flexwing engine,. . . it had been stored for some time, possibly more than a year and not run. He couldn't get it going, so got out of the cockpit and briefed a non-pilot to sit inside and hold his foot onto the wheelbrakes. The pilot then tried to start the engine from the rear,. . .and when it did,. . .it ran over the chocks and away across the field, taking the non pilot bloke with it. He baled out, and the trike ( no wing attached ) continued until it struck a hard object and stopped.

    I cannot understand why anyone would do this. It seems pretty dangerous to me to have a non flying person placed in that situation, and it is extremely good fortune that the chap was not injured by the propeller when he exited the pod.

    No other comments, other than to say that this happened somewhere in the Midlands. . . . .

  2. #2
    Diamond geezer 500 Club
    Join Date
    Dec 2005
    Location
    East Yorkshire
    Posts
    4,434

    Runaway Aircraft. . . .

    Thanks Phil

    Stuff like this happens regularly and I was running-up an engine last night doing tests on a leaning device, so full power running to find peak rpm was a bit scary! Geoff Weighell wrote about fools with engines running out of the trike but I needed to monitor temps and revs

    Wonder if all the superbly inventive brains on here can come up with a procedure or other idea to make ground-running safe? Maybe it's as simple as a rope to a leg on the hangar frame, or perhaps a small heavy structure nailed down that you can park a trike into for this sort of thing?

    Even a cooking 912 is 80hp so will run over chocks, something that digs into the ground would be potentially an accident cause, locking the wheels isn't enough

    A runaway brand new aircraft was destroyed (and it was lucky there wasn't loss of life as the visitor area was crowded) at Rufforth some years ago

    One thought is a couple of those big paving slabs with a ring or eyebolt fixed in the middle, tied to the gear legs, typical static thrust is quite high; even mine's been over 100 kilos with 35hp

    Any ideas?

    Cheers

    Kev

  3. #3
    Senior Member
    Join Date
    Dec 2008
    Location
    Kaunas, Lietuva (Lithuania)
    Posts
    195

    Runaway Aircraft. . . .

    Kev Armstrong wrote: Thanks Phil

    Stuff like this happens regularly and I was running-up an engine last night doing tests on a leaning device, so full power running to find peak rpm was a bit scary! Geoff Weighell wrote about fools with engines running out of the trike but I needed to monitor temps and revs

    Wonder if all the superbly inventive brains on here can come up with a procedure or other idea to make ground-running safe? Maybe it's as simple as a rope to a leg on the hangar frame, or perhaps a small heavy structure nailed down that you can park a trike into for this sort of thing?

    Even a cooking 912 is 80hp so will run over chocks, something that digs into the ground would be potentially an accident cause, locking the wheels isn't enough

    A runaway brand new aircraft was destroyed (and it was lucky there wasn't loss of life as the visitor area was crowded) at Rufforth some years ago

    One thought is a couple of those big paving slabs with a ring or eyebolt fixed in the middle, tied to the gear legs, typical static thrust is quite high; even mine's been over 100 kilos with 35hp

    Any ideas?

    Cheers

    Kev
    Front wheel to a brick wall ... Simple and safe.

  4. #4
    Senior Member 100 Club
    Join Date
    Feb 2015
    Location
    Inside Old Buck ATZ
    Posts
    145

    Runaway Aircraft. . . .

    The ground anchor devices used by off road enthusiasts can hold against a substantial pull (i.e. winching a 2 ton 4x4 out of a ditch).

  5. #5
    Senior Member
    Join Date
    Apr 2007
    Location
    Cambridge
    Posts
    330

    Runaway Aircraft. . . .

    Front wheel against a brick wall not so easy with a fibreglass pod, Kevin's method of tying u/c legs with stout rope to an immovable object is infinitely more practical.

  6. #6
    not real name 500 Club
    Join Date
    May 2006
    Location
    Wing Farm Airfield - Wilts
    Posts
    998

    Runaway Aircraft. . . .

    I always tie any aircraft off to a substatial Fence post when ever we have to do Full Throttle static engine Runs or on A first start up after rebuild install. . No excusses, its always done.

  7. #7

    Runaway Aircraft. . . .

    Hand on the mag switches - it really is as simple as that to prevent most runaways. Do the drills and think about the possibilty and be prepared for it. Aircraft runaway when pilots brain is surprised and then selects neutral freeze mode whilst eyes expand to dinner plate size..

    When starting for flight generally people are disciplined and use the checklist / mnemonic . Seems the most dangerous time is when running with no intention for flight, when brain is then in a different mode and more often than not no checklist or pre start mnemonic is used.

    There have been at least two cases I know of, of brain damage following trike runaways in the UK and it's absolutely imperative to always wear a helmet when running an engine, and be strapped in. The two affected folk were doing neither..

    A few other basics are start up facing a safe ( open) direction so that if it does runaway there is a bit of time to allow for a fumble before ramming anything.

    And a biggy before start is to make sure hand throttle is closed ( should be on the checklist) and push foot throttle down and release and visually check the throttle arms are on the stops (912) or listen for the bottoming click(s) on the two stroke slider carbs.

    I saw a 912 trike runaway at Popham many years back, when passenger was swapped over for a demo flight and hand throttle was knocked open. Pilot didn't check it on start and was facing in towards the display area. Plane shot off through the ticker tape barrier and onto the display stand wreaking havoc and damaging three more planes before smashing into side of a car. Pilot was trying to wring the master key anti-clockwise with all his might..... Pretty much everything done wrong there! - happily no one hurt, though many had to run out of the way!

    If wanting to run up to full power for maintenance checks then generally brakes won't hold it, so using a good thick bit of rope or straps, tie it up round the main gear legs to something substantial - car tow bar, or stout piece of architecture. Of course make sure ropes can't enter prop arc..!

    For homebuilders and tinkers make sure you really grasp that mags switches work the ' wrong way' fit them with the on and off markings that maples / RS supply them with and one will be off and off will be on! - terry Viner made this mistake when cranking his new build Skyranger over in the shed. Throttle was open and with switches 'off' it fired up and went to full chat - brakes weren't beld and protective film was on the screen - and in this state it de hangared itself like a top fuel dragster and shot off into the field. Luckily he managed to switch it off before hitting anything!

    Another mags story - of course if there is any discontinuity in the circuit(s) mags will be live. I did a permit inspection on an alpha and then went to do the check flight. I sat in and asked the owner what particular ritual the 503 liked best for start. He said it liked the prop being rotated by hand to prime, then choke, switches on and should go first pull. He went round the back to spin the prop round, and it started up as he was turning it.. He withdrew hands before losing them, then went very white... Mags were confirmed off but there was a break in the wiring...

    Paul

  8. #8

    Runaway Aircraft. . . .

    Not sure if I have a superb inventive brain but the solution has always seemed obvious to me ...

    Tie it onto your trailer and hitch it to the car.

    All us trike pilot seem to own a trailer, no fuss in buying ground anchors or trusting a fence post.

    Laurie (2)

  9. #9

    Runaway Aircraft. . . .

    For those people with podless trikes who sometimes need to bump start their engine on their own, here's an idea that I came up with. (I should say it's never been triggered so I don't know how it will work in practice)

    I attach a piece of strong fishing line to my single mag switch which is on in the up position. The other end of the line is attached to a tent peg in the ground vertically below the switch. Hopefully if the trike took off at full throttle the line would pull the switch down rather than slip off.
    Mike

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •