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Inadvertent activation of toga during landing roll on a B777 at the end of a long international flight.
| Attributes | |
| ACN | 551538 |
| Time | |
| Date | 200206 |
| Day | Mon |
| Local Time Of Day | 0601 To 1200 |
| Place | |
| Locale Reference | airport : sabe.airport |
| State Reference | FO |
| Altitude | agl single value : 0 |
| Environment | |
| Flight Conditions | VMC |
| Light | Daylight |
| Aircraft 1 | |
| Operator | common carrier : air carrier |
| Make Model Name | B777 Undifferentiated or Other Model |
| Operating Under FAR Part | Part 121 |
| Flight Phase | landing : roll |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp |
| Experience | flight time last 90 days : 210 flight time total : 14000 flight time type : 400 |
| ASRS Report | 551538 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Events | |
| Anomaly | aircraft equipment problem : less severe non adherence : company policies non adherence : published procedure other anomaly other |
| Independent Detector | aircraft equipment other aircraft equipment : tkof warning other flight crewa |
| Resolutory Action | flight crew : overrode automation flight crew : overcame equipment problem other |
| Supplementary | |
| Problem Areas | Aircraft Flight Crew Human Performance |
| Primary Problem | Flight Crew Human Performance |
Narrative:
All night flight from mia to eze. Copilot landed. I took control at 80 KTS. I lowered the thrust reverser levers. I am not sure what I did, but I know that I momentarily moved my hand from the throttles. The fatigue came in to play next because when I put my hand back something was not right, but I was not sure what it was. My hand was hanging there and I felt that it was supposed to be resting on something, so I put my hand on my right armrest. About then, the warning horn started and the flap confign EICAS warning came on. I still did not realize what was going on. That was when I sensed a small acceleration and the fatigue did not matter because instinct took over. My hand went forward, grabbed the throttles and brought them to idle. I disconnected the autothrottles. This is my best guess about what happened. Somehow I touched the toga switches on the front side of the throttles. On the B777 these will only engage below 50 KTS on the ground. My flight home was a scheduled deadhead on a B767 so I have not been able to look at the throttle geometry since then to see how easy it would be to casually touch these switches. Also, I do not know if the sensitivity of the switches is adjustable and I happened to have some super-sensitivity switches. If I engaged the autothrottles without knowing it, I am sure that someone else could do it too. Anyway, having engines that could unexpectedly go to 90000 pounds of thrust on a taxiway or in the ramp area might at least require a warning in the operations manual. The other thing about the fatigue was that I really did not think clearly about what happened until I had gone to the hotel and slept for about 6 hours. Callback conversation with reporter revealed the following information: the reporter has extensive experience in mcdonnell douglas aircraft that has a dissimilar toga activation switch. After further thought and investigation of the position of the switch on the B777, he stated that he probably activated the switch inadvertently due to his fatigued condition combined with his relative inexperience in the aircraft.
Original NASA ASRS Text
Title: INADVERTENT ACTIVATION OF TOGA DURING LNDG ROLL ON A B777 AT THE END OF A LONG INTL FLT.
Narrative: ALL NIGHT FLT FROM MIA TO EZE. COPLT LANDED. I TOOK CTL AT 80 KTS. I LOWERED THE THRUST REVERSER LEVERS. I AM NOT SURE WHAT I DID, BUT I KNOW THAT I MOMENTARILY MOVED MY HAND FROM THE THROTTLES. THE FATIGUE CAME IN TO PLAY NEXT BECAUSE WHEN I PUT MY HAND BACK SOMETHING WAS NOT RIGHT, BUT I WAS NOT SURE WHAT IT WAS. MY HAND WAS HANGING THERE AND I FELT THAT IT WAS SUPPOSED TO BE RESTING ON SOMETHING, SO I PUT MY HAND ON MY R ARMREST. ABOUT THEN, THE WARNING HORN STARTED AND THE FLAP CONFIGN EICAS WARNING CAME ON. I STILL DID NOT REALIZE WHAT WAS GOING ON. THAT WAS WHEN I SENSED A SMALL ACCELERATION AND THE FATIGUE DID NOT MATTER BECAUSE INSTINCT TOOK OVER. MY HAND WENT FORWARD, GRABBED THE THROTTLES AND BROUGHT THEM TO IDLE. I DISCONNECTED THE AUTOTHROTTLES. THIS IS MY BEST GUESS ABOUT WHAT HAPPENED. SOMEHOW I TOUCHED THE TOGA SWITCHES ON THE FRONT SIDE OF THE THROTTLES. ON THE B777 THESE WILL ONLY ENGAGE BELOW 50 KTS ON THE GND. MY FLT HOME WAS A SCHEDULED DEADHEAD ON A B767 SO I HAVE NOT BEEN ABLE TO LOOK AT THE THROTTLE GEOMETRY SINCE THEN TO SEE HOW EASY IT WOULD BE TO CASUALLY TOUCH THESE SWITCHES. ALSO, I DO NOT KNOW IF THE SENSITIVITY OF THE SWITCHES IS ADJUSTABLE AND I HAPPENED TO HAVE SOME SUPER-SENSITIVITY SWITCHES. IF I ENGAGED THE AUTOTHROTTLES WITHOUT KNOWING IT, I AM SURE THAT SOMEONE ELSE COULD DO IT TOO. ANYWAY, HAVING ENGS THAT COULD UNEXPECTEDLY GO TO 90000 LBS OF THRUST ON A TXWY OR IN THE RAMP AREA MIGHT AT LEAST REQUIRE A WARNING IN THE OPS MANUAL. THE OTHER THING ABOUT THE FATIGUE WAS THAT I REALLY DID NOT THINK CLRLY ABOUT WHAT HAPPENED UNTIL I HAD GONE TO THE HOTEL AND SLEPT FOR ABOUT 6 HRS. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR HAS EXTENSIVE EXPERIENCE IN MCDONNELL DOUGLAS ACFT THAT HAS A DISSIMILAR TOGA ACTIVATION SWITCH. AFTER FURTHER THOUGHT AND INVESTIGATION OF THE POS OF THE SWITCH ON THE B777, HE STATED THAT HE PROBABLY ACTIVATED THE SWITCH INADVERTENTLY DUE TO HIS FATIGUED CONDITION COMBINED WITH HIS RELATIVE INEXPERIENCE IN THE ACFT.
Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.