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View Full Version : TO/GA, where does the a/c go?


Lump Jockey
3rd Oct 2003, 02:38
OK, I suppose this is how it works....you decide you want to go around/over shoot, you push the TO/GA button, the aircraft then...? (what, pitches up, and thrust is added automatically, then heads where?) Does it just keep going up and straight, until intervention? And what speed is maintained? Surely the speed is governed by the weight at that time? Please, can someone enlighten me!:(

FatFlyer
3rd Oct 2003, 09:38
depends on type, on a 737-300, on the first press of the TOGA you get reduced go around thrust if the auto throttle is armed, on second push you get full go around thrust as determined by FMC.
IF you are doing a single channel approach, the autopilot disengages, the flight director commands the track the a/c was following when TOGA pushed and commands a pitch up, can't remember what attitude it goes to , as you raise the flaps it pitches down to command the speed for the next flap setting. On a dual channel approach(autoland) the autopilot stays engaged and flies the go around.
if no FD selected it pops up when you press TOGA and dissapears at, I think, 2000ft? radio alt. you then need to select other modes such as level change for pitch and maybe heading select for roll. please correct me if some of this is wrong.

Goodness Gracious Me
3rd Oct 2003, 19:32
The Airbus will fly a fully automatic go-around provided at least one of the autopilots is engaged. A go-around is initiated by advancing the thrust levers to the TOGA position (fully forward) - this then causes the autothrust to apply TOGA thrust, the aircraft will pitch up and maintain the previous approach speed (VAPP ), and will initially follow the track that it was on at the time of go-around initiation.

All you have to do now is raise the landing gear (once you have a positive climb rate).

So now, you are climbing away in a straight line. If the FMGC has been correctly programmed with the go-around track, you can then engage the NAV mode so that the aircraft will follow this go-around track.

At the appropriate height (as programmed in the FMGC - usually 1500' AAL), the aircraft will lower the nose, causing it to accelerate - this then allows you to retract the flaps on schedule. It will accelerate towards its minimum "clean" speed i.e. the slowest speed it can fly without the use of flaps. It will then pitch up again to maintain this speed in the climb.

The go-around altitude "should" ;) have been set during the final approach - if so, the aircraft will level off at this altitude.

So basically, on the Airbus at least, provided everything is correctly programmed in the FMGC, the aircraft will fly a very nice go-around for you - all you have to do is retract the gear & flaps at the approriate points!!

Hope some of this was of use!

Dan Winterland
4th Oct 2003, 04:01
The 744, on pressing the Toga button once will pitch up, apply GA thrust and will maintain runway track if operating to PANSOPS, or maintain runway heading if operating to TERPS. The aircraft knows where you are and applies the correct heading reference. Then, you can heading intervene and select a heading or if you have the MAP loaded into the route as part of the arrival procedure, you can select LNAV.

Boeing 7E7
7th Oct 2003, 00:07
On a visual approach in an airbus selecting TOGA simply increases the thrust to the max setting. It's then up to you to fly the aircraft in the go around. It's much more difficult than simply selecting TOGA with the auto pilot and mangaged nav engaged where it will fly and navigate it for you.

I've seen pilots get their knickers in a twist during a go around because it hasn't been thought through.

I think the previous replies make it all sound so easy. And it is if the auto pilot is engaged. But for those of us who go places where you can hand fly the aircraft without flight directors etc it requires a bit more thought and flying skills!

scanscanscan
7th Oct 2003, 02:17
Sad to say I think the pilots on GF072 would agree with you.