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I am making a down-to-the-1/128th-inch (literally, to the 1/128th inch) model of the Boeing B-29 Superfortress in SketchUp. Starting from zero, I had to make the entire plane up, and to be honest it looks exactly like the real thing at this point. I went down to copying every detail in even the dials and switches and levers, and realized something.

I saw that the pilot can control each of the 4 engines independently. Now, that isn't exactly the problem. The problem, is that the Pilot, "Second Pilot", and Flight Engineer can all control each of the 4 engines. And I can't figure out how that's supposed to work! I mean, can the flight engineer just turn up the throttle whenever? But what if the Pilot is going to speed up so that he/she can reach a higher altitude, but the flight engineer doesn't know that and so he turns the throttle down to decrease engine heat because the cowl flaps are at max degrees for stable flight?

Then there's the issue: If the flight engineer turns the throttle down at the same time that the pilot turns it up, what will the engines do? And I doubt the pilot would speak his every move to the "Second Pilot" and the Flight Engineer to prevent a mix-up. So, does the Flight engineer have to literally request permission and state his/her reasoning to the Pilot before changing the throttle?

And then I thought some more, and realized that the "Second Pilot" also has a "steering wheel", which I know for a fact that other co-pilots have in other planes, but I never knew why. The Pilot can handle the plane's steering by himself/herself, can't they? And even if they couldn't, giving the "Second Pilot" a steering wheel too... well, I can't see how that fixes anything. And if the "Second Pilot" turns the steering wheel at the same time that the pilot does, what does the plane do?

Same thing for the pedals I realized that the Pilot and "Second Pilot" both have. It makes no sense. I get that the "Second Pilot" could take control of the plane if needed because of these duplicate control instruments, but what would happen if they were (accidentally) used a the same time as another? And I also don't get why the Flight Engineer would need to be able to change the throttle. The Flight Engineer literally sits in the opposite direction of the front windows, so it isn't like Boeing wanted the Flight Engineer to be able to fly the plane.

Any suggestions would be very helpful. And, sorry about the gigantic question.

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    $\begingroup$ Teamwork, training, clearly defined roles under a common mission, communication - all lumped under what we now call Crew Resource Management (CRM). Really though, you should try to focus your question on one or two specific areas. Because it is a bit messy now. (Like you just puked up misunderstanding...) $\endgroup$ Apr 22 at 20:19
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    $\begingroup$ It's not just the B-29. Pretty much every plane that carries more than a single person has dual controls. Most can stay aloft for many hours - the B-29 for roughly 25 hours in ferry mode. Suppose your pilot needs a bathroom break or a nap, or gets shot in combat? You'd really like someone else to be able to fly the plane, wouldn't you? $\endgroup$
    – jamesqf
    Apr 23 at 3:13
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    $\begingroup$ "to the 1/128th inch" are you taking into account thermal expansion/contraction of the material? $\endgroup$
    – EarlGrey
    Apr 23 at 7:41
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    $\begingroup$ Also, war. Any one of those stations could turn into a smoking crater, and it would be really nice if the plane could still be flown even if the main pilot's chair is falling towards Dresden. $\endgroup$
    – PcMan
    Apr 23 at 16:10
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    $\begingroup$ Look up the Air France 447 crash, caused in part by invalid dual control inputs. $\endgroup$
    – Ron Jensen
    Apr 23 at 17:08
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In aircraft of this vintage, all the controls are mechanically interconnected. If the left-hand pilot's control yoke/ wheel moves, so does the right-hand pilot's. Likewise for the rudder pedals. And if a pilot or the flight engineer moves a throttle lever, the other throttle lever for that engine will also move.

If several people are exerting different inputs on the same control, then-- "strongest man wins!"

But normally the crew would have an understanding, at any given time, as to which pilot would be flying the plane, and who (which pilot, or the flight engineer) would be controlling the throttles. Standard protocols would be established, and reinforced via training. Normally only one pilot would be "flying", i.e. handling the primary aerodynamic controls (aileron, elevators, and rudder, via the control wheel and the rudder pedals), at any given time. Normally the flight engineer would handle the throttles on this aircraft, in accordance with whatever requests the pilot flying the plane made via the intercom.

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  • $\begingroup$ So, if the flight engineer moves a throttle lever and the pilot catches his lever ghostly moving down and he doesn't want it to move down, he tries to bring the lever back up again, the flight engineer feels the tension and resistance as if someone is trying to stop his lever from moving, and so the flight engineer ceases to move the lever; or something like that? $\endgroup$
    – Ginger
    Apr 22 at 18:53
  • $\begingroup$ @Wasabi -- see expanded version of answer $\endgroup$ Apr 22 at 18:54
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    $\begingroup$ Some of those engine gauges have two needles (one long one short), likely representing inner engine and outer engine. So you can show four engines on two gauges. Hard to see that with them all sitting on zero, you have to look really close. It shows up best on the "oil pressure" gauge on the far left side of the photo. $\endgroup$ Apr 22 at 19:10
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    $\begingroup$ Actually it appears that there are eight oil pressure needles in all (two needles each on four gauges) -- why that would be I have no idea-- might make a good second question-- not all the same redlines etc-- two different oil systems per engine?, something to do with props, or superchargers, or ??? $\endgroup$ Apr 22 at 19:18
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    $\begingroup$ Further to your "strongest man wins" with the purely mechanical linkages, there are cases (combat damage, extreme weather) where both pilots have used their strength together to manhandle the controls in adverse conditions where one pilot on his own was not strong enough. Also as far as controls go, the autopilot could take over control of the mechanical linkage - and in turn, the bombardier's fine-adjustment controls overrode the autopilot guidance. $\endgroup$
    – Graham
    Apr 23 at 13:26
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Quiet flyer is right, here are some more comments to help.

The Pilot In Command (PIC) will advance the throttles for takeoff. The flight engineer's job is then to follow with setting the mixtures and the prop pitches while monitoring oil temps, manifold pressures, head temps and RPM's.

During the climbout, the flight engineer will continually adjust mixture, prop, throttle, cowl flaps and (possibly) turbo wastegate as altitude is gained, according to the published values, and monitor oil pressure & oil temp, and head temperatures.

When the PIC declares achievement of planned altitude, the flight engineer them looks up the book values for cruise at that altitude and ambient temperature and adjusts the aforementioned controls as called for.

If the PIC elects to establish a descent, (s)he will pull back the throttles and the flight engineer then follows up with the appropriate prop, mixture, and wastegate to keep the engines within limits.

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To actually answer the question: the three different positions in the B29 could control the B29 engines at any time to a degree. The flight controls could be controlled by any one of the two pilots at any time. The point is however that they did not randomly do this.

I might add a few random thoughts to the answer here. My background is from a long-time ww2 flyer fan (if you can say such things) and as private pilot in single engine airplanes (Cessna 172 being one example).

First, the crew of a bomber has a single purpose and is trained together. A well-functioning crew will not fight for control. Instead they have different roles during different parts of the flight. American bombers had two pilots; English bombers had only one pilot (someone else could perhaps describe the history of this). It sure is simpler to learn to fly an airplane if there are double controls for two pilots (I remember well my first flight in a PA36 that has only one pilot).

The syllabus used in training, as well as later, is that one pilot is flying, being pilot in control or short PIC. When I learned flying the wording was "You are flying" / "I am flying". During training / learning to fly, the instructor would say "you are flying" and I as a student would be controlling the plane.

This continues into larger planes with two qualified pilots: each pilot had and has different roles in the different phases of flight.

  • Short digression: phases might be as example engine start, warmup, rollout, liftoff, rising, stable flight, deplaning, landing (and so on).

The "pilot-not-flying" might call out heights and speeds and items on the checklist, while the PIC would manipulate the actual flying controls. They work as a team, not as competitors.

Generally, today, large planes have two pilots. Most of the other stuff is handled by the computers. In the B29 days, you needed a third member of the crew, the engineer whose responsibility was to "pamper" the engines, to keep track of and move fuel between the multitude of tanks (the B29 in basic configuration had 11 tanks and you had to manually select to pump fuel between them) and such things. The engines in the B29 additionally had quite a few controls that had to be handled correctly; examples are cooling flaps, superchargers and compressed air for the cabin, propeller settings, fuel settings and so on. I believe that once a stable flight situation was in place (such as en-route), the engineer would be responsible for synchronising the propellers to the same speed and generally keep the engines happy, including monitoring pressures and temperatures and adjusting to the current flight level and outside temperature. This third position, the flight engineer, continued well into the jet era with the early 747-s having that as required crew member.

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    $\begingroup$ The British WWII heavy bombers varied. The Stirling, which was derived from the Sunderland, a long-range patrol flying boat, had dual controls and a flight engineer. The Halifax and Lancaster had only one pilot's seat plus a flight engineer. Since many aircrew were men who'd washed out of pilot training, there was normally at least one who could fly the aircraft. $\endgroup$ Apr 24 at 16:03

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