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FS737Pilot

Anyone got any tips for single engine taxi?

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Hi everyone, so whenever i've single engine taxied, i've always used the #2 engine. I use the apu to supply the left pack, and the rt engine to supply the rt. I always find myself using a ton of thrust to get the 73 moving and i'm pretty sure its canceling out any fuel efficiency gains i should be attaining. so what advice do you guys have? What's the max fuel i should have on board during a single engine taxi? Thanks,Mitch Bowman

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I tried single engine taxi a couple days ago, also with the #2 engine and APU powering the rest.It took almost 40% N1 to get it going, and around 30% to keep it going while also constantly applying right rudder to keep the centerline. FSX doesn't have 100% accurate physics or flight models, and I'm pretty sure PMDG already commented that single engine taxi wasn't realistic in FSX due to it's limitations.

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Most airlines would not want a single engine taxi ! It is better to have both engines started so that oil pressure, vibration levels etccan be monitored. No pilot would start an engine just before going on to the runway without it having beenrunning for a certain period of time.Using a single engine for taxi after landing is sometimes used but very little. Fred.

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Most airlines would not want a single engine taxi ! It is better to have both engines started so that oil pressure, vibration levels etccan be monitored. No pilot would start an engine just before going on to the runway without it having beenrunning for a certain period of time.Using a single engine for taxi after landing is sometimes used but very little. Fred.
Really? All the Continental Pilots i've spoken with have said they use it a lot (mainly after landing)

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Hi guys, Single taxi IN is advertised by the majority of airlines in europe. On the NG you don't need apu for bleed or power. One generator is able to power the plane and by opening the isol valve you will have pressure on both ducts. During taxi out it is not adviseable as you need the engine to stabelize and monitor al systems to operate normally. In real time you'll need aprox 30% of N1 on one engine to maintain speed. Not sure in the sim though!Good luck trying,Jeffrey

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Most airlines would not want a single engine taxi ! It is better to have both engines started so that oil pressure, vibration levels etccan be monitored. No pilot would start an engine just before going on to the runway without it having beenrunning for a certain period of time.Using a single engine for taxi after landing is sometimes used but very little. Fred.
Not really, in the past 3 years at EIN we've really gotten into the whole single engine taxi thing, the more you do it, the more comfortable you get with the procedure, there are obviously seperate procedures that go with it though. In general, the engine will need a 5 min warm up period.Single engine taxi can save a very noticeable portion of fuel in some taxi-outs. Take JFK and it's infamous 40-45 min taxi out for example. I know people have said they only do it on the taxt in, but it's perfectly acceptable to do in on the way out too, just tell ATC that you'll be doing in and they'll almost always be fine with it. There are restrictions on it when LVP are in force but appart from that it's fine. If you think of it this way, single engine taxi out saves you fuel for later on down the route, single taxi in saves the company money in fuel costs. Personally, I just like saving fuel, between globsl warming and helping the company, there's no reason not to. Rónán.

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I always use single engine taxi on the NGX unless it will be a very very short taxi. Every airline i have flown in the US also uses single engine taxi and I have flown a lot lol. My question is sometimes on single engine taxi usually after i have came to a stop (for traffic) and try to start moving again i need almost 60 to 70 n1 to get moving. When I first start moving after engine start the plane only requires about 30. Anybody know what I could be doing wrong?

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Nearly all of the airlines in the US utilize single engine taxi to save fuel. Side note: On the Lear 25, you ALWAYS single engine taxi. Start the other engine when you recieve the takeoff clearence. The reason is that the engines burn more on the ground at idle than they do at cruise thrust at FL410. Very very thirsty engines.

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Most airlines would not want a single engine taxi ! It is better to have both engines started so that oil pressure, vibration levels etccan be monitored. No pilot would start an engine just before going on to the runway without it having beenrunning for a certain period of time.Using a single engine for taxi after landing is sometimes used but very little. Fred.
Really now? ....all that extensive MSFS experience taught you that? lol...do you just make stuff up?

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Really now? ....all that extensive MSFS experience taught you that? lol...do you just make stuff up?
Shocked.gifHypnotized.gifTalking Ear Off.gifLMAO.gifLMAO.gifLMAO.gifLMAO.gif

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Here is an interesting and recent article on the steps airlines are using to trim fuel costs. "For example, low-cost airline IndiGo has advised its pilots to save 100 kg of ATF on each trip by following fuel-efficient flying procedures. "There is a list of procedures that can help reduce fuel burn. For instance, IndiGo pilots have been instructed to taxi the aircraft to the bay on landing on single engine. "Usually, it takes 5-10 minutes to reach the boarding gate and keeping one engine switched off helps reduce fuel burn. "The pilots have also been told to use thrust reverser on idle mode to decelerate the aircraft speed after landing," a source from the airline said." http://www.rediff.co...el/20110816.htm

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- I have a tip for you and its free, which is all its worth anyway Dont do it. FSX does not properly simulate without changing its core code, and good developer wont touch it.

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I tried single engine taxi a couple days ago, also with the #2 engine and APU powering the rest.It took almost 40% N1 to get it going, and around 30% to keep it going while also constantly applying right rudder to keep the centerline. FSX doesn't have 100% accurate physics or flight models, and I'm pretty sure PMDG already commented that single engine taxi wasn't realistic in FSX due to it's limitations.
I've never seen a 738 or 739 type of Boeing taxiing with a single engine running in real world. If you fly with an ATR, it's different.rolleyes.gif By the way, airlines have some written TAXI Fuel amounts for different Aerodromes. But in fact, the A/C doesn't spend that amount of planned Taxi Fuel or spend a bit more depending which taxiway and runway will be used for to be lined up. And, it's important that taxi time (planned also) and its pace make difference seriously for the A/C's takeoff fuel and as you know takeoff fuel can change the A/C's calculated MACTOW.

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Hmm. Never had single engine here in Norway. And I've flewn lots. Only the last meters from taxiway to stand.

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Flew an Airtran 737-700 and we taxied out to runway with 1 engine all the way until about 3 min before departure.

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One generator is able to power the plane and by opening the isol valve you will have pressure on both ducts. Good luck trying, Jeffrey
I'm fairly certain 2 packs - 1 engine is not only a bad joke, but prohibited.

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This was an intriguing question since on my recent United flights I recall the number 2 engine being delayed until we were well along in taxiing. So I asked a 777 FO friend of mine of another major carrier about their procedure. He says it's not standard practice to delay start-up of the second engine since the fuel savings is usually very marginal unless at busy airports like JFK or YYZ in winter where waiting for de-icing and time on the ground is pretty long. Plus, he said if there's going to be any problem with the systems it'll probably be at engine start. So it's best to know that before you get too far away from the gate such that if you need to you can just pull back in, versus being in line during taxiing and nowhere to go. But, as in my case, it does happen outside of those conditions, so it's likely very dependent on the airline SoP. Interesting observations that I'll have to pay more attention to the next time I fly.

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Particularly on the a330, after arrival, single engine is almost a must. That airplane is so overpowered that at idle you'd have to be standing on the brakes. On departure taxi that happens too, and often pilots complain about the brakes getting too hot before take off. Not all companies allow single engine taxi before departure. In 747s it is also very common not to start the two outboard engines. Having said that, in FSX, single engine taxi is impossible to simulate correctly. Single engine taxi in real world doesn't result in the airplane wanting to turn. The tiller doesn't have to be turned to create momenta opposite to the momentum of the engine. In FSX you have to step on the pedal, as if you were flying with one engine. So... I'm afraid that, until they FINALLY (after years and years) simulate proper nosewheel steering, independent of the rudder, single engine ground maneuvers will not be realistic. I'm suprised with some of the pilot comments here. By their nature, jet engines are ready to go right after startup, especially high-bypass turbofans.

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Particularly on the a330, after arrival, single engine is almost a must. That airplane is so overpowered that at idle you'd have to be standing on the brakes. On departure taxi that happens too, and often pilots complain about the brakes getting too hot before take off. Not all companies allow single engine taxi before departure. In 747s it is also very common not to start the two outboard engines. Having said that, in FSX, single engine taxi is impossible to simulate correctly. Single engine taxi in real world doesn't result in the airplane wanting to turn. The tiller doesn't have to be turned to create momenta opposite to the momentum of the engine. In FSX you have to step on the pedal, as if you were flying with one engine. So... I'm afraid that, until they FINALLY (after years and years) simulate proper nosewheel steering, independent of the rudder, single engine ground maneuvers will not be realistic. I'm suprised with some of the pilot comments here. By their nature, jet engines are ready to go right after startup, especially high-bypass turbofans.
Weird... I've never seen an A/C taxiing with a single engine running, including A330, A310, A300 and 747... I tried to simulate the single engine taxiing with NGX and nose steering was OK if GS was about 20-25.

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It doesn't really work very well in fsx due to how its coded, you might get some success with it if you fiddle around with the realistic settings, so you get less yaw etc from single engine, but then that would effect ops when airborne. In terms of it being used in real life, it is done now by more and more ailines, including those flying various versions of the 737, it's used more often during taxi in than out,(there be nothing more embarrassing than getting to the hold to find you can't start engine 2) some airlines are still in the process of testing he procedure to see what benefits they get. Airlines are doing everything they can atpresent to save fuel, as fuel now is the single biggest cost to the operation. Ryanair showed that by flying 170 to 5 dme and gear down at 5 to 4 miles saved them 1million euros a year in fuel across their fleet. So flying cdas, and atc redesigning procedures to get continous climb also are all part of a very changing aviation industry now. Company sops and atc procedures are all focussed now on how to make flights greener. Which is interesting how much flack flying and airports get in the media when actually it's probably the most advanced industry when it comes to doing something about it's environmental impact...cruise ships meanwhile are the biggest inefficient poluting one!

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