Choosing between Airbus, Boeing is a tough call
Question: If you had a choice to fly the Airbus or Boeing, which would you prefer?– Thousand Oaks, California
John Cox: I am asked this question frequently, it is very hard to answer. I flew the Boeing 737 for 15 years and the Airbus A320 for six years and thoroughly enjoyed both of them.
Each had their strong points and their not-so strong-points. The A320 was more comfortable on long flights, because of the larger flight deck and lack of a control column (it has a side stick). The 737 was the best airplane I have ever flown in a crosswind. Both are reliable workhorses of our transportation system. Picking one over the other is like asking me to pick my favorite child ... I like them both!
Q: Some years ago, we had a few back-and-forth exchanges about my concerns as a long-retired airline captain about the various automatic stabilizer trim systems on modern aircraft. You were of the opinion that they were a valuable enhancement. In the light of the 737 Max debacle, do you still feel that way?– Lee Oldershaw, Florida
Cox: The 737 Max issues are very, very complex. In the case of the Lion Air and Ethiopian Airlines crashes, a sensor failed, causing its stabilizer trim to push the nose down. This caused a very unbalanced condition as the pilots were trying to command nose up. The stabilizer trim system normally balances the aerodynamic forces on the tail. But in the two MAX accidents, it was mispositioned by the aircrafts’ Maneuvering Characteristics Augmentation System (MCAS).
The MCAS on those planes also lacked redundancy and did not have a limit on activation. Other automatic trim systems have redundancy and a proven track record (they have been in use since the 1980s). Like any flight control system, the redundancy and testing must be robust for a trim system, manual or automatic.
There are many lessons to be learned from the Max, many of which should help make the next generation of airliners safer and more robust.
John Cox is a retired airline captain with US Airways and runs his own aviation safety consulting company, Safety Operating Systems.