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JammedStab
8th Oct 2013, 12:45
Just curious what your minimum altitude is for dumping fuel?

http://www.aeroinside.com/item/3202/korean-b772-at-dallas-on-oct-6th-2013-engine-shut-down-in-flight

A Korean Airlines Boeing 777-200, registration HL7531 performing flight KE-32 from Dallas Ft. Worth, TX (USA) to Seoul (South Korea), was in the initial climb out of DFW's runway 35L when the left hand engine (PW4090) emitted a loud bang and streaks of flame prompting the crew to declare Mayday and shut the engine down. The aircraft stopped the climb at 3000 feet, worked the checklists, then decided to dump fuel and climbed the aircraft to 5000 feet commencing fuel dump. After about 40 minutes of fuel dump the aircraft returned to DFW for a safe landing on runway 36L about one hour after departure.

sleeve of wizard
8th Oct 2013, 13:00
Boeing FCTM says 4000'
Ops Manual says 5000'
Then you have to consider the state variations ie Min Altitude for fuel jettison in Australia is 6000' :ok:

safelife
8th Oct 2013, 13:04
In europe also mostly 6000 ft

tdracer
8th Oct 2013, 14:55
Back in the 1980's, there was a 747 taking off from London (Heathrow I think - it's been quite a while). Anyway, they over rotated quite badly and both outboard engines surged and did not recover. They managed to circle around and land on two engines, dumping fuel the entire time :uhoh:.

A guy that used to drive KC135s told me that the original turbojet powered airplane (prior to the engine retrofit) takeoff performance was so marginal that if they lost an engine after V1, there was a handle the flight engineer could pull to start dumping fuel out the refueling drogue at whatever the max fuel transfer rate was. :eek:

I'm sure the original question was about the 'legal' fuel dump altitude - just pointing out that sometimes you need to do what you need to do :rolleyes:

Desert185
8th Oct 2013, 15:25
Its my understanding that fuel being dumped vaporizes in 3,000'. ATC seems to like 6,000' as a safety measure.

Given my thought that it is better to dump fuel on the population than an entire aircraft containing fuel, it has been part of my takeoff briefing to initiate fuel dump immediately under certain circumstances.

MarkerInbound
8th Oct 2013, 15:34
Used to do two engine ferrys in 727s. Part of the training in the sim was having a second engine failure at V1. A good FE would be dumping before Vr.

Crazy Voyager
8th Oct 2013, 15:45
Regarding ATC guidance CAP493 says the following:

Fuel Jettisoning
1.77
Pilots of aircraft in flight are permitted to jettison fuel in an emergency.
The decision to jettison rests solely with the pilot but he may request
guidance from ATC.
1.78
When an aircraft in controlled airspace needs to dump fuel, ATC should
co-ordinate with the flight crew:
1.
the route to be flown which, if possible, should be clear of cities
and towns, preferably over water and away from areas where
thunderstorms have been reported or are expected;
2.
the level to be used;
3.
the estimated duration of the fuel dumping; and
4.
the frequency to be monitored whilst the aircraft is dumping fuel.
1.79
Controllers are to recommend to flight crew that jettisoning of fuel
should be carried out above 10,000 feet agl. Exceptionally, if fuel
dumping at this level, or over water, is operationally impracticable or
inconsistent with safety, fuel may be jettisoned above 7000 feet agl
in winter and above 4000 feet agl in summer. For fuel to be jettisoned
below these levels the situation must be unavoidable.
1.80
A vertical separation of at least 1000 feet between aircraft should be
maintained.
1.81
Adjacent ATC units and control sectors should be informed of the
fuel dumping taking place, including co-ordination with units providing
services outside controlled airspace where the aircraft’s track is near to
the boundary of controlled airspace (both laterally and vertically)


http://www.caa.co.uk/docs/33/CAP%20493%20MATS%20edition%205.pdf

flyboyike
8th Oct 2013, 16:00
Considering 14 CFR Part 25.1001 states that an airplane may need to jettison fuel just to meet Part 25.119 and 25.121 climb requirements, I certainly hope there is no minimum altitude.

FE Hoppy
8th Oct 2013, 16:40
Considering 14 CFR Part 25.1001 states that an airplane may need to jettison fuel just to meet Part 25.119 and 25.121 climb requirements, I certainly hope there is no minimum altitude.

Landing climb and approach climb!

You will have already met take off climb requirements or you wouldn't be taking off:ugh:

flyboyike
8th Oct 2013, 17:11
Landing climb and approach climb!

You will have already met take off climb requirements or you wouldn't be taking off



I don't believe I mentioned takeoff, but neither do I see why you're banging your head. It's not like "approach climb and landing climb" start at 10,000MSL or anything.

dixi188
8th Oct 2013, 17:30
tdracer,

You might be thinking of the Contintal 747 at London Gatwick 1st Feb 1988.
You could see the dead grass across the road at the end of the runway, where the fuel had been dumped straight after lift off.
AAIB report here:
http://www.aaib.gov.uk/cms_resources.cfm?file=/4-1989%20N605PE.pdf

Rick777
8th Oct 2013, 17:48
Tdracer. If a Kc135 guy told you anything about a flight engineer he didn't know what he was talking about. I am an old Kc135 guy and we didn't have one. The copilot could dump fuel very quickly though. The check list was: Open the line valve to the boom, close another valve I don't remember the name of, open the dump switch and turn on the refueling pumps. Takes ten times longer to type it than do it. We could and did dump at 6000 lbs a minute. I had an engine blow up at rotation one time and we were dumping by the time the gear was up and locked.

lomapaseo
8th Oct 2013, 17:49
Back in the 1980's, there was a 747 taking off from London (Heathrow I think - it's been quite a while). Anyway, they over rotated quite badly and both outboard engines surged and did not recover. They managed to circle around and land on two engines, dumping fuel the entire time http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/worry.gif.


If you're thinking of a Continental 747 @ LGW, there is quite a bit wrong with the quoted scenario

DaveReidUK
8th Oct 2013, 18:35
If you're thinking of a Continental 747 @ LGW, there is quite a bit wrong with the quoted scenarioI don't think the COA B742 incident at Gatwick is the one being described. That only lost one engine (no 4), not two, during a normal rotation (though it continued to pitch up, to a maximum of 22°, after the engine surge). The aircraft was then airborne for nearly an hour before landing back at LGW.

It did, however, start to dump fuel immediately (even before no 4 was shut down) and continued to do so in the climb to 4000'.

FE Hoppy
8th Oct 2013, 18:47
I don't believe I mentioned takeoff, but neither do I see why you're banging your head. It's not like "approach climb and landing climb" start at 10,000MSL or anything.

There is no requirement to dump fuel and land within a certain time limit and therefore no altitude requirement. As such you would climb to a suitable altitude.

All other scenarios are outside of certification requirements so all bets are off.

tdracer
8th Oct 2013, 19:00
It could well be the Continental event that I was thinking of (although I was thinking it was early 1980s, not late 1980s) - basically going off 25 year old (or maybe older) memory of a second hand account.:uhoh: I wasn't involved in that investigation - just remember hearing the story. I do remember being told that the surge was caused by over-rotation, however the JT9D was notorious for that so it may have been embellishment by the teller....

Rick777 - what I recall KC135 driver telling me was that "they" had a handle to start jettison - I just assumed it was the flight engineer (I am rather surprised to hear the KC135 didn't have one - they must have kept you guys driving busy). As for the 'handle' part - again it may have been embellishment by the teller. A "handle' does make for a better story than a "procedure" ;)

Again, I was just trying to make the point that fuel jettison can happen well below the altitude where the authorities would like it to take place.:ok:

flyboyike
8th Oct 2013, 20:11
There is no requirement to dump fuel and land within a certain time limit and therefore no altitude requirement.


I agree. Therefore, there is no minimum altitude either, correct?

mikedreamer787
8th Oct 2013, 20:53
6,000ft. ..........

BBK
8th Oct 2013, 21:14
Flyboyike

What does your company Ops Manual say?

BBK

flyboyike
8th Oct 2013, 21:42
We don't have any aircraft with fuel-dumping capability, so our manuals are mute on this subject.

flarepilot
8th Oct 2013, 22:09
I remember how they tested fuel dumping way back in the 50's or earlier...

they lit a fire on the ground, flew a plane over it and dumped fuel...turned out 4000' was the minimum magic altitude that the fuel didn't increase the fire on the ground.

of course, as some have said, if you need to dump earlier just to climb, dump!

JammedStab
9th Oct 2013, 13:59
Thanks for the replies. Do most of you plan on a higher altitude to dump if it is cold out. Lets say below 0°C?

Westnest
9th Oct 2013, 14:08
According to company manuals it is 5,000 AGL, in the reference of ATC also.

CONF iture
9th Oct 2013, 16:15
Airbus FCOM
It is possible to jettison in any convenient configuration and at any speed. When feasible, the height should be sufficient to avoid contamination on the ground (5 000 ft AGL is considered as adequate).

FE Hoppy
9th Oct 2013, 16:56
From experience of dumping obscene amounts of fuel on military ops, if you fly into your mates dumped fuel as he passes overhead a couple of thousand feet above it doesn't half stink up the cabin. We couldn't see any noticeable change in TGT and the engines didn't fluctuate noticeably but the windows got a little greasy.

Decided to avoid the trail after the first couple of days just in case.

I can also add that dumping whilst on the ground makes a mess too! Sorry Malmö circa 1992 :(

Desert185
9th Oct 2013, 18:12
Found this. Seems reasonable and inline with what has been discussed.

http://leonardo-in-flight.nl/PDF/B767%20FUEL%20DUMPING.pdf

mikedreamer787
10th Oct 2013, 04:48
Once we had to turn back and dump 80T of fuel after
one of the first class pax had a heart attack. LAX ATC
vectored us over the Pacific and insisted on 6,000 min
altitude (which corresponded to our QRH and SOP
requirements).

6,000 was also for the 727 in Oz so that altitude has
always stuck in my head. Haven't flown a dumpable
aircraft since so my thinking might be outdated a tad.

JammedStab
13th Oct 2013, 16:21
I did just find something by Boeing that says "Fuel Jettison above 4000 feet agl ensures complete fuel evaporation"