How many engines can a 747 lose on takeoff

[Guest JamieG]

Not that you would ever want this to happen in the real world (knock on wood), but how many engines can a 744 lose on takeoff and still be able to get airborne and circle to land safely. My guess would be two, but I'm not positive?

[Manny 1,293]

http://www.usatoday.com/travel/columnist/g...e-captain_x.htmManny

[michal 44]

For the purpose of take-off planning no matter how many engines you have (B52 has 8) you always assume you are going to lose a single engine only. 747 could without a doubt take off with only two engines in some circumstances but that would depend on weight, runway and many other factors.Also "losing" an engine is a highly imprecise statement. It would greatly depend in what phase of the takeoff you would lose it. When you assume that you can lose a single engine - you assume you lose it in the worst moment.Familiarize yourself with V1, VR and V2 - if you understand all the elements involved with a single engine loss you can easily extrapolate this to 2 engines.Michael J.http://www.precisionmanuals.com/images/for...argo_hauler.gifhttp://sales.hifisim.com/pub-download/asv6-banner-beta.jpg

[Guest Callmecapt]

Very interesting question as this is something that happened to me while flying the pmdg 747.I went to the shopping centre to buy some groceries while the missus was taking care of the baby. FS9 was running and I was doing a flight from Miami to Gatwick. I rang my wife to have a look at FS and to see if I had to go Tank to Engine and she said she did see a yellow message on the EICAS that said tank/engine.I told her what to do and she sorted it out for me. Upon my return, I had a look and found that both inboard engines were dead. I brought up the fuel display and saw that both inboard tanks in the wings were dry. The plane was flying on just 2 engines. However, it had gone from 37000 feet to 10000 feet and was still losing altitude, even with full power on those 2 engines. Autothrottle and Autopilot were doing their best to make the plane climb, but no luck. Unfortunatley, I cant remember the load I had, but it wasnt an empty 747.I managed to start the 2 engines by opening the crossfeeds and pumping fuel into the dry tanks. Got my altitude back and balanced the fuel tanks but couldnt continue the flight with just 2 engines. Is this because of FS limitations or the 747?Goran

[Guest s_L_Y_F_a]

talking about engine failures,I was landing in EDDF and got bored by too good wx conditions so decided to knock off 3 engines (2.3.4) on final to see if I would make it..well i made it to runway 7L but it was really really close to a crashI could only hardly maintain speed so I had to descent at a rate of about 500fpm not to stall the queen.at TD I had only about 135 kt!My initial altitude was 2000 MSL speed 200 ZWF 538 with 35000lbs fuel and a distance of about (I´m not sure about this ) 6-7 nmnow my question: Is this realistic? could you really make it under these conditions with only one engine?

[markadeane 272]

After the Air New Zealand DC-10 Mt Erebus crash in 1979, there was a substantial enquiry into the causes and culpability. Amongst the mountains of testimony offered by the airline was a statement that said the DC-10 could have flown from Antarctica back to Christchurch, NZ, on its tail mounted engine alone. This is a 5-and-a-bit hour overwater flight we're talking about here.This evidence was widely disputed and I think Air New Zealand eventually recanted. But it always interested me as to whether such a feat would have been possible, if not advisable.

[Guest Callmecapt]

If any airline wants to try such a stupid stunt, I definitely won't be flying with them. That's what simulators are for anyway.Goran

[Guest JamieG]

awesome thanks--really appreciate all of the detailed responses I've gotten from people

[kmanning 12]

>Very interesting question as this is something that happened>to me while flying the pmdg 747.>I went to the shopping centre to buy some groceries while the>missus was taking care of the baby. FS9 was running and I was>doing a flight from Miami to Gatwick. I rang my wife to have>a look at FS and to see if I had to go Tank to Engine and she>said she did see a yellow message on the EICAS that said>tank/engine.>I told her what to do and she sorted it out for me. Upon my>return, I had a look and found that both inboard engines were>dead. I brought up the fuel display and saw that both inboard>tanks in the wings were dry. The plane was flying on just 2>engines. However, it had gone from 37000 feet to 10000 feet>and was still losing altitude, even with full power on those 2>engines. Autothrottle and Autopilot were doing their best to>make the plane climb, but no luck. Unfortunatley, I cant>remember the load I had, but it wasnt an empty 747.>I managed to start the 2 engines by opening the crossfeeds and>pumping fuel into the dry tanks. Got my altitude back and>balanced the fuel tanks but couldnt continue the flight with>just 2 engines. Is this because of FS limitations or the>747?>Goran>Hi Goran,When you went tank to engine and told her to close the crossfeeds, did you also tell her to swithc off the overide fuel pumps? Some people forget to do this. Ken.

[Guest Callmecapt]

Not really. What happened was, the inboard tanks were way too low and I didn't know it. They had way less fuel than the outboards. So when she went tank to engine, the inboards only had a very small amount to burn while the outboards had more than enough to supply engines 1 and 4 for far longer than engines 2 and 3. Add to that I told her to close the crossfeeds and it was only a matter of time before tanks 2 and 3 went dry.Goran

[kmanning 12]

>Not really. What happened was, the inboard tanks were way>too low and I didn't know it. They had way less fuel than the>outboards. So when she went tank to engine, the inboards only>had a very small amount to burn while the outboards had more>than enough to supply engines 1 and 4 for far longer than>engines 2 and 3. Add to that I told her to close the>crossfeeds and it was only a matter of time before tanks 2 and>3 went dry.>Goran>Hi Goran,Yes, you're correct. The overide fuel pumps used up the fuel faster since the overide pumps were not switched off. These overide pumps are mains two and three. When you get a tank/engine indication on the upper EICAS, you not only close the crossfeeds but also switch off the overide fuel pumps so that the indications on the fuel synoptic on the lower EICAS will remain equal the remainder of the flight, that is, engines 2 and 3 equal 1 and 4. If you have the 747-400 Cathay Pacific video, captain John Grange, I believe it is, demonstates this clearly. Ken.

[Guest Callmecapt]

I have that video. And yes, that's what I forgot to tell my wife. To turn off the override pumps.