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View Full Version : US FAA orders Boeing 777 fix


ChicoG
18th Mar 2010, 06:31
US FAA is issuing an Airworthiness Directive this week mandating a software fix for autopilot flight director computers on 777s to prevent runway overruns on takeoff, Boeing confirmed. "Boeing had received operator reports of flight crews inadvertently engaging the autopilot while on the ground," the company told the Seattle Post-Intelligencer. "When the flight crew inadvertently engages the autopilot during the lower-speed phase of takeoff, the control column forces will be higher than normal when the pilot attempts to initiate takeoff rotation. This can result in a high-speed rejected takeoff, and increases the possibility of a runway overrun." FAA reported that there have been nine aborted 777 takeoffs owing to autopilot computer problems in the last 15 years including two this year. No injuries have resulted. Boeing said it has alerted customers to the need for a fix, which could affect as many as 800 aircraft worldwide. Fixes must occur within three months.

Q: Is this solely done by software, or is there something manual involved? Just wondering how easy it is for a 777 pilot to "inadvertently engage the autopilot on the ground"?

411A
18th Mar 2010, 07:33
Surprising, this.
I would have thought that times had changed...and all modern aircraft could engage the autopilot on the ground (as...that older type can, L1011, in CWS)...excepting, of course, those on the Brit civil register, where it was disabled.:rolleyes::rolleyes:

Ejector
18th Mar 2010, 07:36
Not an overrun, but is this what happened to the Air NZ B777 a month or so ago?

Dan Winterland
18th Mar 2010, 08:30
''...and all modern aircraft could engage the autopilot on the ground''

On FBW Airbus types, AP engagement is inhibited until 5 seconds after takeoff or 50'.

FCS Explorer
18th Mar 2010, 11:25
please read the headline: this is about BOEING :} :}

Sink Rate
18th Mar 2010, 17:14
Autopilot engagement on the ground is normally the result of an accidental push of one of the A/P engagement buttons during the pre flight scan.

HOWEVER there have been a significant number of occasions where the Auto throttle's haven't advanced when the TOGA button was pressed at the beginning of the Take-Off run. This has resulted in a press of the A/T button on the MCP panel to restore A/T operation, before trying to press TOGA again.

In a number of cases the A/P button was pressed instead of the the A/T button thus engaging the autopilot (distractions, high pressure scenario meant that the FMA on the PFD was missed). The auto throttle still wouldn't advance meaning that power would be applied manually, and the autopilot resisted the pull at rotate.

Better FMA awareness is the key but it does seem sensible IMHO to embody this software update.

Best regards,


SR.

411A
18th Mar 2010, 19:43
On FBW Airbus types, AP engagement is inhibited until 5 seconds after takeoff or 50'.


Hmmm, clearly a difficient type.
OTOH, is anyone really surprised?:}

Shock, horror....:bored:

rudderrudderrat
18th Mar 2010, 19:57
How hard do you have pull on a 777 to cause the autopilot to drop out?

fox niner
18th Mar 2010, 21:16
apparently this is what happened in lagos, nigeria in january on an Air France flight.
A/P engagement when lining up, and discovery of their mistake upon rotation.

muduckace
18th Mar 2010, 22:20
Surprising, this.
I would have thought that times had changed...and all modern aircraft could engage the autopilot on the ground (as...that older type can, L1011, in CWS)...excepting, of course, those on the Brit civil register, where it was disabled.:rolleyes::rolleyes:


Please don't tell me that you are surprised that people are getting dumber and hardware is getting smarter.

FCS Explorer
18th Mar 2010, 22:21
i assume the autopilot would revert to "control wheel steering" mode.

wiggy
18th Mar 2010, 22:28
i assume the autopilot would revert to "control wheel steering" mode

Not on the triple, since it doesn't have CWS.

etops skipper
20th Mar 2010, 09:20
If it ain`t boeing I`m not going... better than the "windows" surrounded by an airplane called airbus/scarrybuss, Mr computer, can I turn left, pleaaaaassseeeeeee!!!!:E