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ScootCargoOps
28th Nov 2005, 19:19
Three engines on one wing?

Is this real...


http://images.airliners.net/photos/middle/4/7/8/392874.jpg

Heres another pic...

http://images.airliners.net/photos/middle/0/8/5/379580.jpg

AlphaWhiskyRomeo
28th Nov 2005, 19:25
Yep.

The 747, along with some other aircraft types, were designed to be able to externally ferry non-operative engines for urgent aog cases.

The 747 can take another 747 engine at a specific point under it's wing, as shown, in case one is needed urgently.

As the 747 engines are pretty large, only certain aircraft types can carry them to sick aircraft. So it can be most cost effective to ferry an engine on the wing.

The engine nacelle gets a cover put over it to reduce the drag caused by the spare engine. I believe it doesn't affect costs too much and is much cheaper than chartering a freighter aircraft specifically for the task.

Arkady
28th Nov 2005, 19:25
Real, and not uncommon although you don't see it much in Western Europe. The 3rd (fifth) engine is a spare on a cheap ferry flight.

Edited to say " Damn, beat me to it"

Farrell
28th Nov 2005, 19:26
Yes it's real......The engine is being transported for another plane. It's not used during the flight......happens all the time!;)
The dome inside this engine is just to streamline it in flight.
http://i18.photobucket.com/albums/b140/quartermilefinal/747podd.jpg

steinycans
29th Nov 2005, 01:54
anyone know if there are any special limits for this sort of flight like max speed/alt?

Rocket2
29th Nov 2005, 08:30
Do the RAF still do this with their Tristars? Seem to recall seeing pictures many moons ago.
R2

Swedish Steve
29th Nov 2005, 16:03
When I was working for Gulf Air in the early 80,s we regularly ferried engines from BAH to LHR. But it was very inefficient.
First you had to put 7 tonnes of extra fuel in the opposite wing tank to balance the aircraft, Then you were limited to (I think) 250kts which meant you had to stop for fuel in Larnaca. We tried not to do it on pax flights, or limited the load to the minimum.
I once took a picture of a GF Tristar with a third pod parked on the ramp next to a BA Tristar with a third pod, but sorry I can't find it at the moment.
The Tristar third pod kit was much more difficult to fit than the B747-200. It could take 3 hours to get it right. The B747 went off or on in an hour, and the B747 was far easier to fit and remove, and didn't have the flight limitations.

Dr Illitout
2nd Dec 2005, 13:02
Ah the legendary fith pod!!!
This was one of those idears that looks good but in fact has so many downsides to it that most airlines choose to either three engine ferry the aircraft back or to hire a freighter. The cost of the equipment and the disruption to the operation being the main ones.
I was on the 747's for four years a while ago and I never saw one done. I did hang a fourth pod on a Tristar once and I will confirm what Swedish Steve says by saying it was a long back breaking job that I would not choose to repeat!!
Hears a question ,can the 747-400 carry one?

Rgds Dr I

SMOC
3rd Dec 2005, 09:52
Yep

http://www.airliners.net/open.file/289429/L/

sstaurus
5th Dec 2005, 23:48
How about a GE-90 engine? :}

I-Fly-River
6th Dec 2005, 02:12
hey guys,

since you're in this topic, just wanna ask. I've seen a photo of 747 flying with only 3 engine, but i cant remember where. can anyone confirm this please? thanx.

Dr Illitout
8th Dec 2005, 12:13
Found it!!!

http://forum.keypublishing.co.uk/showthread.php?t=14479&highlight=engine+ferry

The story is that during an engine change they found that the pylon was cracked. So they flew it to a repair shop like that!. I would love to have been a fly on the wall when they broke the news to the crew!!

"Aircrafts fueled Captain and the daily has been done. Oh there's just one more thing..........."


Rgds Dr.I

I-Fly-River
8th Dec 2005, 23:45
Dr I,

Thanx! I was looking for that... I wonder how they flew that aircraft out of there.... must have been quite an interesting flight!

cavortingcheetah
9th Dec 2005, 12:22
Some little time ago when I wrote Flight Planning for the ATPL licence, the 747 ferry graphs were in the schedules provided and we got flight planning questions on it.
Hope this helps.:D

interestedparty
9th Dec 2005, 13:11
Also intriguing was the 3 engined VC10, with one RB211 (port side I recall) and the normal complement on the other side of the tail...............

Scottie Dog
9th Dec 2005, 15:15
Also recall seeing a BOAC Super VC-10 at Manchester with a spare engine in a very streamlined pod under the left wing.

Out of interest why does it seem to be the left wing that is always used?

Scottie Dog

Dr Illitout
9th Dec 2005, 17:03
Don't know for certain but I'll hazzard a guess that they want to keep the area around the freight bay doors clear. That will enable the loading and the 5th podding can happen at the same time. As I said its only a guess it could be rubbish

RGds Dr I

BossEyed
12th Dec 2005, 09:10
interestedparty, the difference of course is that the RB211 VC-10 (G-AXLR) was a trials aircraft used for development of the engine, rather than in use an operational ferry task.

It caught the attention, though.

http://www.vc10.net/History/Individual/Images/GAXLR_air_med.jpg

Sir Richard
12th Dec 2005, 10:20
In the early days of the 742 we 5th podded from LHR to MIA, with very little information, but it worked ! Subsequenly an ASI overlay was provided with the speed limits for future flights (290kt / M 0.85 I believe) Above those speeds a light harmonic vibration was noticed. For added interest it was the first flight in a 742 for all of us. (G-BDXB 9/8/77)

The original plan was to route via JFK, but the Captain wisely suggested non-stop which was easily achieved. Sorry about the 20+ staff pax who were offloaded !

I think a photo even made the front page of the Miami Herald - "5 little engines" was the caption if my long term memory is accurate. :8

p.s., The 3 engined VC10 and 5 engined Vulcan (Olympus for Concorde) were regularly seen in the Filton Area many moons ago.

BossEyed
12th Dec 2005, 18:29
Whilst I'm finding engine testbed pics:

5 engined Vulcan (Olympus):
http://www.transportarchive.org.uk/aimages/G1633.jpg

5 engined Vulcan (RB199):
http://www.avrovulcan.org.uk/903/903_199front.jpg

Same airframe (Vulcan B1 - XA903).

There was also a Pegasus testbed Vulcan, I believe. Anyone have a picture of that?

Lou Scannon
18th Dec 2005, 13:25
I flew a DC10 once from Los Angeles to Gatwick with a spare engine under the left wing close to the fuselage. It had fibre-glass cowlings built around it to reduce drag.

I remember that it only reduced the cruise speed and increased fuel burn by very small amounts.

The only problem was the time it took to mount and un-mount the contraption.

barit1
18th Dec 2005, 14:07
Back to carting a spare engine -

Here's (http://www.aviationpics.de/tech/tech.htm) some upclose shots of a 4th pod on a DC-10-30. (DLH methinks)
(Scroll halfway down the page)

CV880
21st Dec 2005, 23:58
Engine Out Ferry (inoperative engine still fitted) is available as a Flight Manual supplement for most 3 and 4 engined aircraft but not all operators opted for it. It was not part of the basic Flight Manual.
A previous employer of mine experienced 747 pylon damage away from base and Boeing offered to 3 engine ferry (with engine missing from damaged pylon) back to base. We opted to replace the pylon where the incident occured as there were reasonable facilities available. Back in the 60's a colleague's wife told him she saw a DC8 with only 3 engines fitted landing at Long Beach. He scoffed and said maybe only 3 smoke trails ie. one engine inoperative, but next day had to eat humble pie when he found a DC8 had been ferried in with a damaged pylon (no engine fitted) for repair.
Lockheed L1011 3rd pod went under the right wing just to be different. L1011 performance penalties and limitations for 3rd pod use were fairly severe compared to 747.