Q400 Problems Get Worse

Differences? Most likely maintenance procedures. Did SAS follow all procedures correctly, or at least the same way as other operators? The investigation will likely find this out, but these things, of course, take time.

It might be that Horizon Air has a more complete maintenance program, being that they are owned by the same company that owns Alaska Air and Alaska Air flies into some of the harshest mainline airports in North America.

Alaska Air got into trouble over that jack screw issue when their MD-88 when down off California, so they had to make changes to their maintenance programs. Those changes would likely have affected Horizon Air as well.

am a retired flight controls engineer. I have been following the Q400 accidents that occurred in Denmark and Lithuania very closely and consider these accidents to be very critical situations. These failures are giving the aircraft industry a subtle, but urgent warning that must be addressed. I found a report, dated September 15, 2007 online re – Preliminary Report on I am a retired flight controls engineer. I have been following the Q400 accidents Danish SAS Q400 accident that included a very useful drawing for analyzing the failure mode. It would also be very useful to review a drawing or sketch of the main landing gear retract/extend actuator, manufactured by the Goodrich Corp. in Tullahoma, Tennessee in order to confirm my analysis of these failures. Please note that a nose gear incident occurred on a Q400 in Japan on March 13, 2007, and I suspect that it is probable that it contains a similar actuator design as the main landing gear system. Another nose landing gear accident occurred in Munich, Germany on September 21, 2007. If this is true, it would be very important to inspect the nose landing gear actuator as well as the main landing gear actuator. In my study of the main landing gear reports, some investigators noted the fact that the jam nut backed off and the lockwire was missing. This condition, could eventually cause a disconnection of the rod end, which was also stated by investigators in preliminary reports. This failure may have actually occurred after 10,000 cycles while coupled with severe impact upon landings. This scenario seems very plausible. Most of the hydraulic actuators used in the aircraft industry contain a locking device to prevent rotation of the actuator piston, and are secured by a jam nut, and lockwired to prevent the jam nut and the locking device from backing off. Early discussions regarding this failure were stated that corrosion in the linkage probably played a major role in the accident. I don’t believe that corrosion played a significant role in these failures. My intention is not to interfere with the official investigation of these accidents, but to offer a feasible scenario to help solve the problem.

Now let me get this straight???

SAS suspends flying their Q400s while the rest of the airline world continues to fly them without incident. Then just yesterday, SAS flies one again and the landing gear collapses again. Today SAS announces they will discontinue using their Qs.

Who are we kidding? This is a SAS problem.

I truly believe this problem is related to SAS or airlines that have poor maintenance policy or control. I found this bit of information on the web:

16 JAN 2006 SAS aircraft flew without inspections
Scandinavian airline SAS said it was tightening up the inspection and servicing of its planes after Swedish authorities identified gaps in its safety checks on 10 aircraft. The aircraft hadn’t been inspected according to international regulations after engine installations. The Swedish CAA reported that the company`s international operation permit could be limited or withdrawn as a result of the misconduct. SAS said the problem could partly be due to the fact that some of the maintenance had been outsourced to other companies. (AP, Reuters)

It seems odd that most of the landing gear problems is coming mainly from one airline-SAS!