4 engine aircraft starting sequence

[pjpahs]

With the recent video of the Berlin Airlift Historical Foundation C-97 engine startup and flight I noticed that the engines were started with #3 then #4 , #2, #1. I found on UTUBE many other 4 piston engine aircraft using the same engine start sequence. FIFI, DOC, TWA Connies, Lancasters, C-54,B-17, B-24, etc. There has to be a sound reason for this. Is it safety, or maybe the accessories on certain engines, such as generators or hydraulic systems that have to start before others? I sat in the Hughes flying boat this last July and the guide asked me what the "E" and "H" meant on each throttle , and I answered correctly Electrical and Hydraulic , yeah I remembered it from an article , didn't win a pony.

[Christer]

How are the engines numbered? I guess the designer decides or is it the same on all multiengined aircraft?

[John Dupre]

I believe they are numbered 1 through 4 from left to right from the pilot's view in the cockpit. I remember hearing an old timer make this point once, "What's the critical engine on a B-17? Whichever has a working generator!"

[Robbie Stuart]

The preferred sequence for starting multi engine piston aircraft, is starting the engine which is closest to the battery location. (And Hope It Has A Working Generator)
Robbie

[warbirdfinder]

The critical engine on a B-17 is #1 engine. The B-17 has a generator on each engine, so losing one barely effects the electrical system.

Normally the engine or engines nearest to the batteries is started first.

When 4 engine jets, B-707, etc. were started at the gate,, #3 and #4 were started first. This allowed the agent a few minutes more to pull back the jetway in the event any passengers needed to board at the last minute.

[Stoney]

When I flow C-54s it was 3, 4, 2, 1, and and on taxi in shut down 1, 4

[Airlift48]

Stoney is correct. 3421. Shut down whichever 2 don't have hydraulic pumps to save fuel and wear and taxi in on two.

In the C-54, the hydraulic pumps are on #2 and #3. You need them for brakes, steering, flaps, windshield wipers, and cowl flaps.

[CAPFlyer]

In "commercial" aviation (including bizjets and turboprops here), typically you start the right side engine(s) first for 2 reasons. First, they're typically the closest to the batteries and/or GPU connection. Second, since the door is usually on the left side, so it allows you to have passengers board while starting an engine or if there is an issue you and your passengers can get out through the main door and not have to worry about "emergency exits". There are a few smaller bizjets that will run the right engine if there's no GPU available so that they can run the air conditioning on the ground to keep the cabin cool for their passengers arrival because the fuselage blocks a lot of the sound of the running engine, so it won't be uncomfortably loud for them.

You'll also find that most APU's exhaust out the right side of the airplane for the same reason.

[Christer]

Quoted from Johns post:

I believe they are numbered 1 through 4 from left to right from the pilot's view in the cockpit.

and from Stoneys post:

When I flow C-54s it was 3, 4, 2, 1, and and on taxi in shut down 1, 4

I understand that as starting the engines on one side, the innermost engine first and then the other side, the same sequence. On shutdown, basically the reversed order.

[CAPFlyer]

The sequence is to start both engines on the right wing starting with the inner and then outer, then start the two on the left wing (inner then outer). Then you shutdown the outer engines after landing for taxi in. It helps keep taxi speed more controllable since you're much lighter than on takeoff. This is fairly standard for most 4-engine piston aircraft and even some 4-turboprop aircraft.

[marine air]

On the tri-engined Falcon 50 , we start the second, then third, then first.

[b29flteng]

Inboards are started first, if you have the outboard running and start an inboard which starts on fire, now you have to shut the outboard down before anyone can get near the inboard to fight the fire. On taxi with FIFI, Doc, or the C-97 the outboard propellers are only about 22 inches above the ground. Most northern airport taxi lights and signs are high enough to clip with the propellers.