Couldn't do what? Pull the stick back into a stall? Sure you can. Under normal law you can't do that with an Airbus, that's one of many things that caught the AF crew off guard.
There's no such protection on the 737. Nobody's done that because unlike on the Airbus, it's never safe to do so. There are, however, plenty of ways to get caught off guard in a 737 and stall it. Take a look at the UTAir and Thomsonair go arounds that got their planes to about 45° nose up. Or the 737 Air Florida planted right into the Potomac because they didn't have the elevator authority to avoid the stall. Or Fly Dubai…
As for human interactions, the 737 is a series of bad choices (especially the MAX). Take a look at the Helios Air crash, the pilots were confused by an alarm that could mean two different things. Unfortunately hypoxic pilots aren't known for their reasoning ability.
Couldn't have both pilots fighting each other on the controls (hard nose-up vs. hard nose-down) without knowing about it, since the yokes are physically linked (unlike sidesticks).
yes, this is what i meant. i should have been clearer in my original statement.
here is what happened in the airbus air france incident:
- one pilot had the sidestick full hard nose up, the other full hard nose down.
- neither pilot realized what the other pilot was doing.
on a boeing airliner:
- the controls for each pilot are physically linked.
- if pilots try to put “their” yolk into an opposing position, they will start having to physically wrestle for control.
- this type of failure mode of the air france crash wouldn’t have happened in a boeing airplane; the pilots would have realized what was going on within seconds.
general note:
- when flying, it is highly unusual for both pilots to be giving input into the controls at the same time. one pilot “has the airplane”, the other is there to assist, help with the radios, planning, etc. the handoff between who “has the airplane” is very deliberate. this was another failure mode of the air france flight.
- but my point still stands, the fact that the controls are linked makes the gp point a bit moot.
> this type of failure mode of the air france crash wouldn’t have happened in a boeing airplane; the pilots would have realized what was going on within seconds.
Say what? Atlas Air face planted a 767 with pilots doing just that:
> The captain’s and the FO’s opposing elevator control
> forces continued for about 10 seconds, during which the
> airplane’s dive continued to steepen. Thus, the NTSB
> concludes that the captain’s failure to command a positive
> transfer of control of the airplane as soon as he attempted
> to intervene on the controls enabled the FO to continue to
> force the airplane into a steepening dive.
Or the Air France thing that's now on the front page. In a Boeing 777.
Poor training is poor training. Physical feedback is not a safety benefit. It sounds nice in theory but in practice doesn't do much. You can easily say the same thing about A vs B thrust levers, look at that Sriwijaya Air crash. The Boeing design sounds more intuitive until you look at crashes where the feedback didn't do a single thing to help the pilots or avoid a crash.
The sidesticks aren't linked on an Airbus but there is a "DUAL INPUT" alarm. If you're already panicked enough to ignore a dual input alarm you're likely to ignore stick feedback from someone countering your inputs.
There's no such protection on the 737. Nobody's done that because unlike on the Airbus, it's never safe to do so. There are, however, plenty of ways to get caught off guard in a 737 and stall it. Take a look at the UTAir and Thomsonair go arounds that got their planes to about 45° nose up. Or the 737 Air Florida planted right into the Potomac because they didn't have the elevator authority to avoid the stall. Or Fly Dubai…
As for human interactions, the 737 is a series of bad choices (especially the MAX). Take a look at the Helios Air crash, the pilots were confused by an alarm that could mean two different things. Unfortunately hypoxic pilots aren't known for their reasoning ability.