Mentour Forum

What’s Wrong With Boeing?  


Road Runner
Joined: 3 weeks ago
Posts: 1
04/02/2020 11:42 pm  

Mentour, I need to take exception to several things you said in your video “What’s Wrong With Boeing?”


First, when the 737 was designed (1966), it is not a true statement to say that Boeing “didn’t care how much fuel was used”.  That’s utterly ridiculous.  Of *course* they cared how much fuel was used.  Why else would they have chosen what was at the time the most fuel efficient turbofan engine available, in the form of the JT8D?  The stance of the 737 on its landing gear was influenced by the desire to have the aircraft’s cargo hatches close to the ground, true, but that was not the overriding reason for it.  Given the engine technology of the time, the use of the JT8D, and the patented (by Joe Sutter) way the engines were mounted, the landing gear were made exactly as long as necessary, and no longer.  Nobody in 1966 had even a clue that eventually something like the CFM56 would even exist, so how could they have anticipated it and given the 737 longer landing gear?


Secondly, you state as if it is fact that the A320’s landing gear was made longer than the 737 in anticipation of newer, larger, higher by pass turbofans.  Again, not supported by evidence.  The A320 was designed in 1982-85, and the CFM56 was the biggest small turbofan available at the time.  I don’t think anyone in the industry was anticipating the LEAP or the P&W geared fan engines in 1982.  In fact, I know they weren’t.  The A320 was designed for the CFM56 and V2500, period.  Airbus engineers didn’t have a crystal ball any more than Boeing’s did.  The only difference is that by the time the A320 was being designed, the 737 was already a world-beating design, and had been in service for a decade and a half.  


You need to be more careful with your facts in the future.

Dennis Cirrotti
Joined: 1 week ago
Posts: 1
15/02/2020 8:57 pm  

How did Boeing create this tragedy answered. 
With the new MAX 8 design having a pitch up tendency in manual flight during a turn unlike the previous 737, the MCAS was required to certify it as a 737. The function of MCAS was to trim nose down in a manual flight turn to give it the same flight characteristic as the previous 737 and not require new pilot certification training. Boeing saw this as a certification modification and a not need to know system to the pilot and did not publish it’s design or the operating function in the flight manual. Boeing justified this because MCAS may never be activated in flight, because the system is only active when the autopilot is off and the flaps are up. Also, the fact that the aircraft is almost never manually flown without the autopilot in-gauged at cruse altitude when the high and low speed stall margin is only 4 to 6 knots above cruise speed, Boeing considered this an internal non-pilot function. If Boeing had just published a system description and emergency procedures if an uncommanded activation of MCAS occurred at a low altitude and at speeds well above stall, to simple extend the flaps to inhibit MCAS, Both Lion Air Flight 610 and Ethiopian Airlines Flight 302 would have returned safely. With that, the cause of the malfunction would have been identified and the engineering fix applied as is normal in the airline industry. You can not create an automated system that effects the way the aircraft fly's without telling the operators and pilots how it works.

Captain Dennis Cirrotti