Beech Weekly Accident Update

Piston Beechcraft Accidents 

4/13/2017 through 4/26/2017

Official information from FAA and NTSB sources (unless otherwise noted). Editorial comments (contained in parentheses), year-to-date summary and closing comments are those of the author.  All information is preliminary and subject to change.  Comments are meant solely to enhance flying safety.  Please use these reports to help you more accurately evaluate the potential risks when you make your own decisions about how and when to fly.  © 2017 Mastery Flight Training, Inc.  All Rights Reserved

THE WEEKLY ACCIDENT UPDATE IS AN INDEPENDENT PRODUCT OF MASTERY FLIGHT TRAINING, INC.


New reports this week

4/16 1815Z (1315 local Sunday afternoon): A Be58 “went off the taxiway and [its] nose gear collapsed,” while taxiing at Perryville, Missouri. The solo pilot was not hurt; airplane damage is “unknown”. N6040R (TH-1026) is/was a 1979 Baron 58 registered in Little Rock, Arkansas.

("Taxiway excursion”—this will result in at least two replacement propellers and two engine teardowns…possibly enough to total the Baron for something as “minor” as going off a taxiway. Keep your eyes outside while moving on the ground. Program your GPS, run your checklists, configure your airplane, and anything else that requires head-down time in the cockpit before you move away from your start-up point or after you stop in the run-up area. “Don’t text and taxi.”)

4/19 1440Z (0740 local Wednesday morning): A Be36’s landing gear collapsed during landing at Phoenix, Arizona. The two “flight crew” avoided injury, and the Bonanza has “minor” damage. N24158 (E-1214) is a 1978 A36 registered in Queen Creek, Arizona.

(“Gear collapse during landing”)

4/19 1800Z (1200 local Wednesday noon): Two aboard a Be23 escaped injury despite “substantial” airplane damage, when the Beech “went off the runway, down an embankment and into a fence,” during an attempted takeoff from a private airstrip near Fallon, Nevada. N786KS (M-1676) is/was a 1975 C23 registered in Reno, Nevada.

("Runway overrun/failure to climb during takeoff””; “Substantial damage”—might density altitude have been a factor for this mid-day departure? The public-use Fallon airport is at just under 4000 feet MSL, and although the Sundowner is a great ride [I flew one with a student from Wichita to Oshkosh and back one year] it does not have a lot of excess power even if leaned for maximum.) 


New NTSB reports this week

Events previously reported in the Weekly Accident Update

4/10 A36TC autopilot/trim/control system failure at Livermore, California.  From the report:

A Beech A36TC landed gear-up at Livermore Municipal Airport, Livermore, California after the pilot experienced a flight control malfunction during the landing approach. The commercial pilot was not injured, and the airplane sustained minor damage. The local personal flight departed Tracy Municipal Airport, Tracy, California, about 1015. Visual meteorological conditions prevailed.
 
The pilot stated that he departed earlier in the morning from Livermore with the intention of performing a "warm-up" flight. The preflight checks were uneventful, and after departing, he flew northeast for about 30 miles. He then turned southwest towards Tracy with the aid of the autopilot. As he approached Tracy, he disengaged the autopilot, and performed four uneventful landings and takeoffs. He then departed west towards Livermore, again using the autopilot after he had trimmed the airplane for level flight. He contacted the Livermore Air Traffic Control Tower, and was given a straight-in clearance for runway 25L.
 
Shortly after contacting the tower, he disengaged the autopilot using the autopilot disconnect button on the control yoke. The airplane immediately pitched aggressively up about 50 degrees with an immediate loss of airspeed. The pilot stated that the pitch up happened so fast that he feared the airplane was about to stall. He applied full forward pressure on the control yoke, and the airplane pitched almost directly nose down, and began to quickly build airspeed. He then reduced the yoke forward pressure, and the airplane pitched back up again.
 
The pilot reduced engine power, set the landing gear selector switch to down, and extended the flaps. He stated that he heard the landing gear extend, and confirmed that the three green landing gear lights had illuminated. With full forward yoke pressure, he was able to maintain an approximate level attitude, although the control forces were so great that he needed to use both hands and his knee to keep the yoke forward. He then called the tower, declared an emergency, and was given an amended clearance to land on runway 25R.
 
He attempted to reach over to the autopilot circuit breaker, but it was out of his reach, and because of his hold on the yoke, he feared he would immediately lose control of the airplane if he released his grip.

He previously experienced an engine throttle cable failure, and suspected that this time the elevator control system had either stuck or failed. The pilot reached down to adjust the elevator trim wheel, but it would not move, and he could not safely move himself into a position to look down and observe the elevator tab position indicator. He continued the approach, and regulated pitch by adjusting engine power, and holding the yoke fully forward. The airplane continued to porpoise as he initiated a gradual descent back to the airport.
 
He stated that at some point during the approach and ensuing struggle, he inadvertently knocked off his glasses and headset, so was no longer able to hear the tower controller. Although the tower controller made multiple calls during the final approach warning the pilot that the landing gear was not extended, but the pilot did not hear those calls due to his loss of the headset. The airplane touched down on runway 25R, and it was then that the pilot realized the landing gear was not extended. The airplane came to a stop on its belly and the pilot immediately egressed. An airport operations staff member immediately responded to the airplane, and turned off the master switch, magnetos, and fuel selector valve. He noted that the landing gear selector switch was in the down position, and the landing gear and auxiliary fuel pump circuit breakers were both tripped.
 
Post-accident examination revealed that the elevator tab gauge indicated "18U" (up), and the elevator tabs were in the tab down (airplane nose-up) position. The airplane was equipped with dual controls. Examination revealed that with the yoke in the full-forward position, the yoke T-bar obscured the view of the lower center portion of the instrument panel, blocking the view of the elevator tab indicator, and obscuring left seat occupant access to most of the circuit breakers, including the autopilot and trim breakers. Additionally, while holding the yoke fully forward with an extended left arm, it was not possible to reach the autopilot and trim circuit breakers. 

Most autopilot systems in Bonanzas can (and do) carry control force against the trim at times. In other words, they can “push” or “pull” a little on the controls, and do not always trim pressures completely off. That’s why the airplane is often a little out of trim when you disengage the autopilot—it’s expected, and you have to be ready for it, especially if you fly a coupled approach to or near minimums. 

The amount of “push” or “pull” the autopilot is capable of is limited, however. Most in Bonanzas can exert no more than about 30-35 pounds of force against the trim. This is designed (1) so the autopilot does trim, at least some, instead of running the servos continually to exert brute force on the controls, and (2) so the autopilot knows to disengage if it gets into a situation where it has to exert excessive force against the trim system. If the maximum force necessary to command the airplane where the autopilot “thinks” it should be, the system will disengage. This comes without prior warning, and hands the pilot a radically out-of-trim airplane…much as seems to be the case in the accident cited above. 

The NTSB’s report of the pilot’s statements, coupled with the trim indication found during the investigation, suggest these possible scenarios:

1. The autopilot reached its maximum control force limit and disengaged. The pilot entered into an inflight pilot-induced oscillation in an attempt to recover.

2. The autopilot reached its maximum control force limit and disengaged. A physical control system failure occurred, jamming the elevator controls (including trim) in a nose-up position.

3. The autopilot for some reason did not disengage, and the pilot fought it all the way to the ground.

4. Some very unusual electrical system failure caused autopilot/servo malfunction in addition to other electrical overloads.

Points to ponder:

- Did the pilot push and hold the autopilot disconnect/trim interrupt switch on his control yoke? Holding this switch removed electrical power from the trim servos, a temporary “fix” to trim runaway until the pilot can manually retrim (assuming it is possible) and then pull the TRIM circuit breaker.

- Was the pilot familiar with the location of the TRIM circuit breaker? In Bonanzas it is the second or the seventh breaker from the right on the copilot’s subpanel, unless it has been moved in the process of avionics upgrades. This is the only breaker that the pilot needs to be able to find from memory, without having to look for it, for the very reasons this crash report state. Many airplane owners use a breaker tab or even a twisted bread-bag tie wrap around the breaker to help them find it in an emergency. 

I’ve detailed before how I teach, and practice on the first flight of each flying day, looking at the attitude indicator, holding down the autopilot disconnect/trim interrupt switch on my yoke, and locating and pulling the TRIM circuit breaker by feel alone. I did this for 25 years before I needed it right after takeoff one day—and it was instinctive for me to complete the emergency procedure and get the breaker pulled quickly when my trim ran wildl nose DOWN from a point about 50 feet above the runway during takeoff. It’s that important

- The landing gear anomaly and the popped circuit breakers discovered by investigators may be clues to a deeper electric system malfunction that affected the autopilot and electric trim system.

- If because of some larger and wildly unusual electrical system failure pulling the TRIM breaker does not fix the problem, or extreme circumstances prevent you from reaching the TRIM circuit breaker (such as in this event), turning off the battery master switch is an alternative to remove power from the trim servo motors. This is not mentioned in the autopilot/trim system POH supplements, but it should be.

-  During a normal landing solo or with two in the front seats of an A36TC, if you trim off the control forces after full flap extension on final approach as most pilots do, you’ll find the normal A36TC/B36TC/turbonormalized Bonanza elevator trim position is 18 to 21 units nose UP. This is why a go-around in one of these airplanes requires a hefty push forward not he controls to avoid pitching up into a pwer-on stall when you apply power for a go-around.  It’s unclear why the pilot was not able to control the airplane normally with a trim condition normally encountered when landing an A36TC.

I commend the pilot for bringing the airplane in for a landing after experiencing such wild pitch excursions and control forces while close to the ground  on final approach. Hopefully the NTSB will have resources to determine the ultimate cause of this mishap.Until then, consider the points above as ways to avoid or combat similar, if not necessarily identical events.

Change “Gear up landing” to “Autopilot/trim/control system malfunction”.


2017 SUMMARY: Reported Beechcraft piston mishaps, 2017:

Total reported: 47 reports

Environment: (Note: FAA preliminary reports no longer report weather conditions)

Operation in VMC:  20 reports 
Operation in IMC:    1 report  
Weather “unknown” or “not reported”:  24 reports
Operation at night: 5 reports    

Most Serious Injury
Fatal accidents:  5 reports 
“Serious” injury accidents (not involving fatalities):  3 reports 

Aircraft damage
“Substantial” damage:  10 reports
Aircraft “destroyed”:   8 reports


By Aircraft Type      

Be35 Bonanza  8 reports
Be36 Bonanza  7 reports 
Be55 Baron  7 reports     
Be58 Baron  6 reports  
Be23 Musketeer/Sundowner/Custom III  3 reports 
Be33 Bonanza/Debonair  3 reports 
Be76 Duchess  3 reports 
Be17 Staggering  2 reports   
Be18 Twin Beech  2 reports  
Be 19 Sport  2 reports 
Be60 Duke  2 reports  
Be45 (T-34) Mentor  1 report   
Be95 Travel Air  1 report


PRELIMINARY DETERMINATION OF CAUSE
(all subject to update per official findings):

Landing gear-related mishaps (22 reports; 50% of total reports)

Gear collapse during landing  
9 reports (Be18; Be33; two Be35s; two Be36s; Be58; Be60; Be95)

Gear up landing  
5 reports (Be33; Be36; Be58; two Be76s)

Landing gear collapse during landing//known mechanical failure  
2 reports (both Be55)

Gear up landing or gear collapse/alternator/electrical failure  
2 reports (Be35; Be58) 

Gear up landing/known mechanical failure  
2 reports (Be55; Be76)

Gear collapse during taxi  1 report (Be55)

Gear collapse during touch-and-go  1 report (Be55)


Impact during landing (9 reports; 20% of total reports)

Landed short/Collision with obstacle on final approach  
2 reports (Be35; Be45)

Loss of directional control during landing/Snow/Ice 1 report (Be58)

Collision with animal on runway
2 reports (Be35; Be36)

Loss of control during landing  1 report (Be55)

Landed long/runway overrun  1 report (Be35)

Hard landing  1 report (Be19)

Landing/unknown  1 report (Be23)


Engine failure (6 reports; 14% of total reports)

Engine failure in flight  
3 reports (Be17; Be33; Be35)

Engine failure during takeoff/initial climb 1 report (Be36)

Engine failure immediately after takeoff/multiengine aircraft  1 report (Be55)

Engine failure during missed approach in IMC  1 report (Be18)


Impact during takeoff (3 reports; 5% of total reports)

Runway overrun/failure to climb during takeoff  
2 reports (Be23; Be36)

Takeoff/Unknown 1 report (Be23)


Miscellaneous (3 reports)

Taxi into object/another aircraft  1 report (Be19)

Taxiway excursion  1 report (Be58)

Autopilot/trim/control system malfunction  1 report (Be36)


Stall/Spin/Loss of Control In Flight (2 reports; 5% of total reports)

Stall/spin/loss of control in flight during multiengine training  1 report (Be60)

Stall/spin/loss of control during low speed practice  1 report (Be35)


Unknown (2 reports; 5% of total reports)

Crash/Unknown  
2 reports (Be17; Be58)


Recognize an N-number?  Want to check on friends or family that may have been involved in a cited mishap?  Click here to find the registered owner.   Please accept my sincere personal condolences if you or anyone you know was involved in a mishap.  I welcome your comments, suggestions and criticisms.  

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