The reason why shall we say the procedures are so immature and geriatric compared to the other cards I suspect is because the original system from outset was pretty much bullet proof.
You have a great big lump of a DC jack screw powered off the emergency battery bus, way more robust than it needs to be mainly because it acts as ballast weight down the back for trim, saves having a lump of depleted uranium in the tail which in the old days when they used it for ballast. Three wires, one rocket switch, CB, and cut out switch (which I suspect was only used by technicians, never in anger). The manual trim system is "fly by wire" all of which are steel and the control runs are over pulleys.
I suspect the whole 737 series has had issues with that trim system that you can count on one hand since the 1960's. Nobody ever used that card so there was never a need to update it. The option of going paperless flight deck like the 777 and 787 was discounted due to grandfather issues. Just finding the QRH book behind the captains seat takes time. Then finding the correct page takes time. Paperless as soon as it see's that the trim has been running more than 5 seconds the QRH card will pop up on the 6th screen. 737 is a Memory item which is never trained for in the sim.
I suspect that a solo software fix onto the screw jack input wasn't the first solution either, a secondary motor onto the trim line with a clutch that could be over powered by the main trim system I suspect was looked at. But they were struggling with weight so that got ditched.
Yaw damper systems (which are used on the rudder to counter act dutch roll) were initially like this screw jack setup, they took the data off the Captains heading double integrated it, and then waggled the rudder to counter act the issue. When it was in the rudder pedals were solid you couldn't move them, to the point I had a US trained FO going into Dubai similar to the calibrator that's crashed recently who hit vortex and ripped his thigh muscle trying to push the rudder pedal to lift the wing. His crime was forgetting to press the AP disconnect twice to kill the yaw damper as well as the AP on a J41.
These days you can use the rudder pedals normally to there full limits with the yaw damper in and you never think about it really until a cap comes up and you have to slow down to the YAW damper u/s limits. To the extent you can actually have an engine failure and if you spot it winding down you can feed in the rudder to counteract the yaw and the AP never needs to come out. The BAe Jetstream rudder system was a wire analogue system. You really didn't want to play with swapping your heading flux valve input though with yaw damper in, this could give instantaneous heading changes which the yaw damper system would drive the rudder hard over to the yaw damper limits. You tended to only make that mistake once.
BTW the MCAS system is only the tip of the iceberg in relation to the Elevator system now. Its what the media and discussions are focusing on because its what's highlighted the issues with the elevator system design. The whole NG series is now under the microscope. If the FAA are making them tackle the elevator size and power and the size of the trim wheel in the cockpit its a whole different ball game. The FAA might have no option if its proved it certified the NG's as compliant when they weren't. The FMEA for the increasing the size of the stab and keeping the same sized elevator and reducing the size of the trim wheel in the front is the one that's going to be interesting. I suspect the MCAS software change has already been done. The delay is dealing with the bigger picture with the whole of the NG series, which is a tyrannosaurus in a china shop issue, there are over 7000 of them out there on the planet. They have an extremely good safety record mechanically. The only thing that pulls them down is the number of pilots that have taken them off road on landing due to poor decision making in regards to weather conditions and/or pushing a unstabilised approach. Personally I see no point changing them. They have proved themselves safe the hard way.
What they are going to do with the max's tail I really don't have a clue. Its a catch 22. The system works fine and pilots don't screw it up as proved by history of type if there is no external input to the trim system. Add in external input and it vastly increases the chances of system irregularities which vastly increases the chances of the pilots screwing it up. The current control and power is more than fine for normal operations and likely failure modes as the NG has proved. The new mode of failure its not. Get rid of the external input problem solved but then the aircraft isn't stable at high alphas. Which to be fair does happen way more often than passengers know or expect. And if your expecting 737 NG pilots to swap between the 800 and max sometimes in the same day its going to bite at some point if there is a change in control forces. There are things called noise abatement procedures which most airports have in built up areas. It requires you to fly a sub optimal profile to try and reduce the noise. It usually has you climbing at high draggy alphas at V2 +10 until 3000ft sometimes with a low level power reduction as well as cleaning up the flaps. This leads to highish alphas but I don't have a clue if they would be in the MCAS zone. here is a link to the Boeing noise profiles. The only time you can deviate from them is if you have an emergency or weather related issue. Zurich in Europe the company will get a 5000 euro fine if you don't comply with them. And if the company doesn't pay then they will come chasing after the Captain for the cash. They are particularly trouble some because they require a hard turn at low level as well requiring a 25 angle of bank as well because of rich powerful locals that live off the ends of the runways. There are something like 30 noise microphones as well dotted about which if you trigger them you also get a fine even if you have carried out the procedure to the letter. So your angle is high anyway to get V2 +10 and increases again because your in a 25 deg banked turn which gets you to within 20knots of Vs which is really high alphas and I pretty certain you would have the MCAS in action if you were stupid enough to try and fly a NDAP2 manually.
You just have to look at EK521 777 crash in Dubai, that was 14000 hours experience on the flight deck and they still screwed up something which is trained for and done 3-4 times in the sim every 6 months. Although I have my suspicions that the temperature was way above what the airport was reporting due to local labour laws. Add in variations in control forces into the equation which occur on no other type from Cessna 150 trainer through to 747-800 and its not going to be pretty. Go arounds are not that common at most airports. The likes of Gatwick they are aiming at 1 an hour. If its more than 2 then the controller will be looked at, 0 and they will also be looked at because they are not pushing the traffic in hard enough. 1-2 an hour and they are doing great. But for a pilot you looking at 1 or 2 a year outside the sim for a regional pilot flying 4 sector days and 800 hours.
So I agree Hemi that this will be the subject of case study's for years both from design POV and from The pilot side of things. Hopefully lessons will be learned and money doesn't override safety.
