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ACW599
17th Nov 2006, 10:33
We were sitting in the crewroom the other day watching the horizontal rain and setting the world to rights. Somewhere along the line we got on to talking about Frederick Forsyth's short story 'The Shepherd', and this led us on to the modern equivalent.

In the FIH (page 6 in the current version) there is a procedure in which, if you lose both transmitter and receiver, you fly a left-handed equilateral triangle and "watch for interception by a shepherd aircraft". Unless my rapidly fading memory is playing up, this procedure has been around for a very long time. But has it ever been used in anger?

Chugalug2
17th Nov 2006, 11:58
This procedure was infamous for its ineffectiveness, the effect of wind on the triangles causing them to be anything but on a radar plot meaning that you could fly them until you ran out of fuel without alerting shepherds, sheep dogs, or sheep. Indeed I used this very infamy in a brilliant piece of court room drama on my JC&SS course (long ago, as are all my tales!). The lad was banged to rights, flying low over a village, witnessed by the local PC (an ex Observer Corps member, just to twist the knife!). We of the defence team were faced with the insuperable task of getting him off, an outcome that had eluded all previous courses, IIRC. As the only GD/P it fell to me to come up with a scenario that could allow for a reasonable cause for his conduct. It was then that I remembered said procedure, and how our lad might reasonably abandon it to descend VMC (just) to below the overcast (low) and circle the nearest town or village to fix his position before triumphally returning to base without a stain on his character! If that all failed we had a panoply of VIPs held in reserve as character witness' to plead for the poor boy. No need, unanimously found not guilty by the Members of the Court Martial, outstanding and morally upright paragons of virtue all! Scenes of uncontained joy ensued from one and all, with the exception of the prosecution team, who had unimaginably based their case on law. Muppets!

raytofclimb
17th Nov 2006, 13:22
The procedure also assumes that the shepherd aircraft can find you, join up, give suitable hand signals and lead you back. Then you have to fly close formation until VMC below. No mean feat if you were never taught it.

How many civ pilots could do that? HEFOM code, whats that?

Very interesting case in March this year when an F3 took a twin with total electrics failure into Leuchars. The (twin) pilot didn't have a clue- couldn't even remember the instructions about being intercepted and didn't do anything to help the F3 lead him in.

Ray.

BEagle
17th Nov 2006, 14:46
My old and bold QFI at the premier UAS (hint - based at White Waltham) told me never to bother with the triangle business...

"Just find the nearest airway and orbit underneath it - that'll get the buggers' attention!"

This was, of course, long before RAF Learning Command light aircraft had transponders.

stillin1
17th Nov 2006, 15:44
7600 / 7700 and fly under / near CAS is the best idea. The chances of anyone noticing you pottering around in triangles is less than a very small number:cool:

Chimbu chuckles
17th Nov 2006, 17:00
My father was a Sgt Pilot flying Vampire FB-7 or 9s in 1952/3 ish and suffered a complete electrical failure at night over the Bristol Channel..I think transitting back from Europe somewhere...he apparently flew triangles until near fuel exhaustion and then rolled inverted and bailed out. The aircraft being sans ejection seat. He bobbed around in his raft until the Ark Royal found him after sun up.

After reading the Forsythe book as a teen I asked him about it...he said it was one of those things that sounds good when you read it in the manuals but loses some of it's shine as the fuel runs out and no bug ger has turned up...reckoned he would have been most pleased with an ethereal Mossy:}

He's a retired QF pilot now...giving 74 a shove and in rude health:ok:

Rossian
17th Nov 2006, 18:31
I'd almost forgotten about that story. Mid '70s, sunny summer day in Cornwall my wife was sitting in the garden reading this very tale. Co-incidentally (yes, we checked the times) I was in a Nimrod plunging earthwards out of controlled airspace over southern France with total electrics failure whilst arguing with a senior passenger who claimed "you CAN'T lose the vital bus-bar". When it was suggested that he took a closer look at the eng's panel and found an explanation for ALL the the doll's eyes being cross-lined, he persisted in his arguement. Surprisingly, he took umbrage at my suggestion that if that was the sum total of his useful contribution to our worsening situation that he return to his seat and STFU until we got on the ground in one piece. After an amusing couple of days at Istres-le Tube we continued our merry way to Malta. The faulty relays were much admired and sent back to the makers with the question "why do you think they are all half open/shut with these feathery crystals growing between the contacts?". Their answer was "Dunno". "Why not?" "Sop is to take a GS screwdriver and crack them all to the de-energised state; did this. And they worked perfectly afterwards. Dunno."
Madame said she felt the hairs on the back of her neck rising when I called from Istres to say we were OK and why we were there. Spooky, or what?

henry crun
17th Nov 2006, 20:00
The C/O of a transport squadron was going VFR from A to B one day and decided to test the procedure.

He called up the ATC unit and said "I have flying left hand triangles for 30 minutes now, why has no one has appeared to shepherd me".

The reply came back "Ah, that could be because our radar is notamed off for maintainance today".

Pontius Navigator
17th Nov 2006, 20:56
Another good procedure that proved ultimately useless was night search.

Start leg, close eyes, fire green very. Wait for glow to fade, look for red flare. At 4 miles per minute that is 2-3 miles with eyes closed on a visual search.

20 miles, 5 minutes later same procedure. 'nother 2-3 miles with eyes tight shut.

Now with the visibility 20 miles you might have a chance. With visibility at 3 miles and less - no chance.

The procedure was clearly designed for open ocean search in good visibility and probably good weather to find downed aircrew. Looking for a ship - no chance.

4Greens
17th Nov 2006, 21:02
If you can get a dead WW2 pilot to fly up and rescue you, why would you worry about flying triangles?

ACW599
17th Nov 2006, 22:27
>If you can get a dead WW2 pilot to fly up and rescue you, why would you worry about flying triangles?<
So I take it that the consensus of the thread is that however long I fly left-hand triangles over Telford in my mighty Vigilant, a Mosquito with 'JK' on the fuselage will probably not appear and escort me back to Cosford. Oh well, dream on.
Mind you, the stalling speed of a Mosquito is probably higher than Vne in a Vigilant, so we might have had a bit of a problem anyway.

waldorf
18th Nov 2006, 05:34
It is extremely unlikely that a controller will be able to distinguish a radar return flying triangles from amongst the usual background of other radar returns from ac conducting GH or going about their normal business in the ever shrinking and heavily congested Class G airspace. Even in relatively uncongested airspace, and as previously mentioned, the wind effect invariably transforms the neat triangular pattern you might hope to achive on the radar display into a drifting smudge making it almost impossible to spot!
Many years ago at Linton, I was discussing this very issue in the bar with a friend (a tame QFI) and we decided to try it out. In short, the plan was for him to fly triangles while I watched the radar display (having been off console for some time) and try to pick him out from the 20 or so other similar types all of which were wearing the same conspicuity squawk. The 'experiment' was conducted in relatively uncongested airspace (Vale of York) at night. Despite my best efforts, I was unable to distinguish the 'target' at first. However, subsequent attempts (following te breaks)proved more successful. The 5000ft wind was, if memory serves, only 20kts.
Many years later while staring at a radar display waiting for someone to call for service when I noticed a fast moving cotact flying in circles and wondered if he was as bored as I was. This went on for some time and
remembering that night at Linton I eventually put a call out on guard attempting to contact the aircraft to see if all was well. The crew replied with surprise as they had been flying triangles just to test the theory that no one would notice!