The LP cock
 

Can't remember why I went to LHR that day. My base was LGW, flying Daks and Herons. For whatever reason, on my day off, I had to drive to Heathrow. Coming in from the Hounslow direction, I saw a growing column of black smoke rising from the middle of the airfield; too much for a practice by the Airport Fire Service.

Later, I learned that the crew had done a great job doing 5/8 of a left-hand circuit and landing north-eastwards on Rwy 05R, having taken off to the west on 28R. In due course, it was said that the one mistake was that they had failed to close the LP-cock (low-pressure fuel valve) of the engine that had caught fire. As a copilot with no jet experience at that time, this meant little to me.

Apparently, though, the LP fuel valve was at the beginning of the fuel line from the fuel tank to the engine. It was closed by pulling the fire handle, prior to firing the first of 2 fire extinguishers. At the other end of the pipe, at the engine itself, was the HP-cock (high-pressure fuel valve). The crew had successfully closed this when they shut the engine down, using the same lever that is used on a normal shut down.

When the burning engine fell away, however, there would have been nothing to stop fuel pouring out of the severed fuel pipe at the top of what remained of the engine pylon.

3 years later, I converted to the BAC/Vickers VC10, which has slightly more powerful versions of the Conway engine than Whisky-Echo had. The flight-engineer’s fuel panel (designed circa 1963) was/is logically laid out, like a schematic diagram, with switches and indicators showing the positions of the various valves; including the LP valve for each engine. During and after a fire drill, there could be little doubt what was the position of the relevant LP valve.

After another 4 years (1975), I went on the Boeing 707-320C (not BOAC), with Pratt & Whitney JT3D turbofans. But I doubt the F/E’s fuel panel was much different from Whisky-Echo’s, even though ours were newer aeroplanes − also built well after our VC10s. When I saw the indication system for the LP valve, I was dismayed. The only indicator was a dim blue light. When the valve was open, the light was off; when the valve was closed, the light was also off (yes, this is not a typo).

The only indication of a change in the position of the valve was that the blue light came on WHILE THE VALVE WAS IN TRANSIT. So, if the flight-engineer was distracted for the few moments while the valve was in transit, there was no way of satisfying himself that the valve had run shut. And if the fire handle had not been pulled properly, there was nothing on his panel to warn him (and the captain, who can also see the flight-engineer’s panel) that something had not been done; that needed to be done.

Round about 1976, our B707s started to be modified; to improve the LP valve position indication…

IRC the LP cock could be closed by the Fire handle or the LP switch on the F/E panel.

The BOAC initial drill was -
1. Thrust lever closed- to avoid shutting off the wrong motor.
2. Start lever cut off- hp valve at the engine
3. Fire Switch (handle) pull- trips the genny, shuts the hyd pump supply off, closes the lp cock(if IRC also the hp electrically) and arms the extinguisher cct.
4. Fire off the first extinguisher if the fire still evident or a fire warning.
5. 30 secs, fire off the second shot and if no joy speed up to get the fire to leave the scene. Great idea but we believed Boeing at the time!
F/E then announces phase one complete and reads the check list aloud to double check all is done.

Later on, cant remember when, he then switches off the LP cock switch on his panel (this should do nothing as it was already closed but it was belt and braces)and announces light on dim. The valve had a blue light. Bright for transit, dim for closed. Push to test dim produced a bright light thus checking the bulb was ok and the valve closed.

This is all 30 year old memory but as a trainer I seem to remember this still-sad git!

It could be that WE was not modified as my history only goes back to 1970.
Straightfeed

Hi straightfeed,

The drill you remember certainly sounds in line with my memory from 1975-77, on the -320Cs.

But on most of our aeroplanes (BCAL), the ones with the blue light, it was on only when the LP valve was in transit. The modified light, if memory serves, was white. It was bright when valve in transit; dim when valve closed. Maybe yours were different.

It certainly would be interesting to know the exact mod state of the fuel panel on G-ARWE, but my present dial-up connection discourages me from trying to find the original AIB report.

Chris

Wasn’t a contributory factor the location of the fire handles on the ex Cunard Eagle aircraft being different to the standard BOAC aircraft and just who was responsible for pulling the fire handle?

P5 as opposed to the glareshield but I can’t recall which had what.

You remember correctly, PanAmerican and standard Boeing procedures about the same.
The 707 was a reliable old aeroplane, but it did require proper procedures to be followed, least you end up in a heap.
The Captain on WE did quite a commendable job.
These old aeroplanes were not easy to fly, compared to later designs.

P5 location was a customer option, made standard, as I recall, on later models.

Inspection found that none of the fire handles had been pulled, boost pumps for the main wing tanks and fuel shut off valves were still on. The "fire" and "failure" checklists were identical, with the addition of cancelling the fire bell and pulling the fire handle in the fire case. Confusion stemmed from "failure" being called first and then changed to "fire" at the same time as the Check Captain making the suggestion to call a mayday.

I've been expanding the Wikipedia article on the accident today. Reading this thread, it looks like I'll have to get the book too!

http://en.wikipedia.org/wiki/BOAC_Flight_712

Super VC-10 - Someone who knows how to expand Wikipedia. :ok:

When you next get bored please see

http://en.wikipedia.org/wiki/List_of_RAF_stations

A Prune thread, below, pointed out several ommissions from this list - including Binbrook. Could you correct these?

RAF Stations (past and Present) - Biggest, Best and Bonnyist??

http://www.pprune.org/forums/showthread.php?t=321144

RAF Binbrook is on the list, and has its own article. :)

http://en.wikipedia.org/wiki/RAF_Binbrook

VC-10, My apologies for using this thread - from the RAF Stations thread, .......

mystic_meg said "Binbrook was obviously a figment of my imagination then... "

Binbrook wasn't then mentioned. It is now.

My suggestion was - I have to confess - the list wasn't from memory I borrowed it from Wikipedia http://en.wikipedia.org/wiki/List_of_RAF_stations

Perhap if we leave this a few weeks for more additions then someone who understands editing Wiki could do just that.

....... and I've just noticed RAF Bahrain (Muharraq) under United Arab Emirates. Not so.

Wiki still needs more work. :)

Forget, you could always be bold and edit the article yourself. You don't need to join Wikipedia to edit articles. :)

Just to let you know, the article on the accident is currently featuring in the "Did You Know?" section of the main page of Wikipedia, and will be there for the next 6 hours or so. :)

http://en.wikipedia.org/wiki/Main_Page

For those who may not have seen it the last flight of WE is described in a profusely illustrated, six-page article in the current (June 2008) issue of The Aeroplane magazine.

It includes a very dramatic colour photo taken by an ATC officer of it landing back minus number 2 engine with the port wing aflame.