747 central tank safety

[ZAGORFLY]

Is whole issue of Central Tank possible explosion on the 747s is finaly closed?
which modification to the existing fleet have occured?
At CX (HKG, if somebody can tell) the 747s are safe regading this topic?

[TURIN]

Of course they're safe, they are still flying aren't they?:\

[BOAC]

Cannot comment on the 747, but the 737 NG had similar problems and limitations placed on the minimum fuel contents of the centre tank at various stages of flight. These are cancelled when modified pumps (or wiring?) are installed.

[18-Wheeler]

Yep they're all safe now.
The pumps have been changed and the procedures for using the last few tonnes of fuel is also different. Been that way for over five years I think.

[lomapaseo]

Yep they're all safe now.
The pumps have been changed and the procedures for using the last few tonnes of fuel is also different. Been that way for over five years I think.
Mostly agree, however the all safe part is relative since the best that can be done is only to minimize risk to a practical extent. And the practical part is in the eyes of the beholder

[Intruder]

New fuel management procedures are in effect for the 747 Classic, somewhat restricting the use of the center tank pumps, mainly at low center tank fuel loadings. I suspect this will be permanent, as I doubt Boeing will spend the $$ to certify a "permanent" fix unless the FAA requires it.

Dunno 'bout the 744, or how the 748 will be different...

[cyco]

TWA was shot down by the US navy on a naval exercise gone wrong, with the center tank blamed to cover the whole thing up, but I didnt tell you that.

Must go now before they find me.

Remember the truth is out there :}

[vapilot2004]

TWA was shot down by the US navy on a naval exercise gone wrong, with the center tank blamed to cover the whole thing up, but I didnt tell you that.
Must go now before they find me.
Remember the truth is out there :}

Too many people would have been involved - without gulags and death threats - impossible to cover up !

I have always doubted the final outcome of the investigation. Could have been an elusive third party with less sophisticated weaponry than the USN.

[Grunf]

Hello.

Mods done on '47s are not enough (different pumps, different porcedures). Procedure change for the CT is Ok but suggestion by NTSB was to get the vapors inert i.e. to neutralize them.

That system is installed on large military cargo a/c (C-5 for example) and the outcome was very, very obvious in the Dover crash (no fire and all the crew was soaked in fuel).

therefore like so many other NTSB recommendations the overall airline industry is ignoring it as too pricey.:\

Cheers

[Mad (Flt) Scientist]

The safety requirements now being imposed on fuel tanks with respect to vapours and sources of ignition, if applied consistently to other systems, would probably ground every commercial aircraft, economically if not legally.

To suggest the industry is dragging its feet over cost is nonsense; the issue is acceptable risk - which is about one catastrophic event per 10,000,000 flight hours, historically, and as embedded in current regulatory and safety practices - and the politically motivated over-concentration on specific risks - like inflight TR malfunction or fuel tank ignition, to name two cases - probably overall degrades safety by distracting attention from the easier-to-address or more significant risk contributors.

[lomapaseo]

The safety requirements now being imposed on fuel tanks with respect to vapours and sources of ignition, if applied consistently to other systems, would probably ground every commercial aircraft, economically if not legally.
To suggest the industry is dragging its feet over cost is nonsense; the issue is acceptable risk - which is about one catastrophic event per 10,000,000 flight hours, historically, and as embedded in current regulatory and safety practices - and the politically motivated over-concentration on specific risks - like inflight TR malfunction or fuel tank ignition, to name two cases - probably overall degrades safety by distracting attention from the easier-to-address or more significant risk contributors.

Bingo!:D

Made even more so by the use of resources (manpower, equipment, etc.) far beyond just throwing money at it.