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eng1170
13th Jun 2002, 23:03
Very simple question (I hope) ? On a Go-around what comes up first flaps or gear? Question specifically for a/c such as Boeing 737/757 etc. And is there any a/c that are specific exeptions to this. Work in the big metal shed and don't get out much!!

You bend 'em, we'll mend 'em! :)

M.Mouse
13th Jun 2002, 23:22
SOP on the 757/767 in my company is Flaps 20 and gear up once positive rate of climb established.

I don't really mind if you have a stoush with someone based on what they have posted, but pre-emptive strikes are a little unfair! :)

Fresca
14th Jun 2002, 00:15
Yebb....Same here. My SOP (757) says G/A switch pushed. Flaps 20, positive rate gear up. The same was for the 737 put if I remember correctly it was to flaps 15

'%MAC'
14th Jun 2002, 00:49
Yup, every aircraft manual I’ve seen is ‘bout the same. The idea of a go-around is to get it climbing (best way to do that is to add power and clean it up).

Not being the brightest star in the sky I came up with a mnemonic, to help me remember the procedure. PAFLAF (works with BE-1900, EMB-120, B-737, DC-10)

exempli gratia
P- Power (max - duh)
A- Airspeed (generally an additive to a ref speed, i.e. Vref + 15)
F- Flaps (retracted to your max allowable t/o position)
L- Landing gear (up on positive rate call)
A- Airspeed (increases due to configuration changes mentioned)
F- Flaps (again, this time retracted on climb-out schedule or all the way)

Yup, Fresca, On the 73 it be flap 15, max t/o or if OEI, it be flap 1.

Do there be some issues with 411A, M.Mouse? :)

[edited, 'cause JT brought up some good points, as usual]

Hogg
14th Jun 2002, 02:18
B727, G/A pressed (if fitted), go-around thrust, flap 15, positive climb gear-up.

Simple as that!:cool:

Hogg

john_tullamarine
14th Jun 2002, 02:25
I think that there is a little more detail to be considered ... the sequence is landing configuration to missed approach configuration (considering landing and approach climb WAT matters .. especially for the OEI case or that possibility) and, subsequently through the clean up process.

We need to keep in mind that, while the aircraft is certificated for a missed approach with landing flap and wheels down for AEO .. the OEI case is only addressed for approach flap and wheels up. The actual numbers and flap position sequences will be Type specific.

The end result is not much different to what others have described above .. but the philosophy is.

dolly737
14th Jun 2002, 07:53
B737:

1. PF: Press TO/GA, call "Go-Around, Flaps 15", PNF: Monitor N1, position flap-lever, call "Flap 15 set", when indicated
2. Both pilots: Verify G/A attitude, mode annunciation, thrust set
3. PNF: Call "positive rate" when indicated by VSI and altimeter
4. PF: Call "Gear up"
....

Captain Stable
14th Jun 2002, 09:48
On a late call for a go-around it's quite possible to touch down. I've done it. You need the gear for that, or it gets a little messy.

So I would be very dubious indeed of any SOP's that called for the gear to be raised on a go-around before establishing positive climb.

Hogg
14th Jun 2002, 11:52
In John Tullamarines post above he mentions OEI and AEO?? Never heard of them before!

Please explain for less intelligent mortals.

WAT still Weight Alt Temp?

Hogg;)

I taut eng1170 just wanted a simple answer :rolleyes:

mustafagander
14th Jun 2002, 12:09
"OEI" - One Engine Inop

"AEO" - All Engines Operating

I think it's almost universal in big jets for G/A

G/A thrust, F20 (for B747)

Rotate to G/A attitude and monitor speed

+ve RoC, gear up

Check/set missed appr altitude

Navigate the G/A track (LNav if you have it)

At cleanup alt, commence clean up

Nightcap
14th Jun 2002, 12:28
Lads lads , ive got it sussed, because I get very nervous on Go-Arounds, my technique is as follows:


250 knts to 6 miles, gear down boy do the paxs get a fright with the noise etc, then down the glide clean, with bout 75%N1, as i get to goaround, i firewall the thrust levers, haul the nose up to about 30 degrees, then just before i bust the goaround altitude which ive forgotten to set , raise the gear and really push hard over and at the same time slapping the levers closed.

works everytime but the skippers dont like it that much:p :p

john_tullamarine
14th Jun 2002, 12:41
The WAT limits are the minimum airworthiness design standards climb gradients (1st, 2nd, 4th segment min gradients and 3rd segment capability, approach and landing overshoot minimum climb gradients) which are intended to give some small climb capability and which go into the takeoff and landing weight calculation process.

The gear horn will come on with flap beyond approach and gear not down as a warning for landing mis-configuration.

As Capt Stable notes, the risk of a temporary touchdown is very high for a low level missed approach ... those who are Cat 2/3 qualified will know all about this ....

eng1170
14th Jun 2002, 16:33
Thanx for a nice selection of answers everyone! Was playing around on Flt Sim on PC and wasn't quite sure, but as Capt Stable points out the big bouncy bits with the round rubber thingy's do come in handy if it's a late G/A. I now fully understand the quadrant gates on the 73 at 1 and 15 units flap - thanx again all!:cool:

Intruder
14th Jun 2002, 18:42
747-400:

Go-around thrust, rotate, Flaps 20
Positive climb, gear up

Ignition Override
15th Jun 2002, 07:52
During go-arounds, most pilots don't push the throttles nearly as far forward as they (we) should.

And in some old Douglas jets, after "go-around power" is set, "flaps 15/20 etc" and "pos. rate" stated before "gear-up", don't forget to "disarm the spoilers".

Making a very short, boring p.a. to the passengers and cabin crew can help calm them help them understand that it is a normal (due to extra caution) and not an emergency maneuver.

"You want another approach checklist, just to be on the safe side?"

*Lancer*
16th Jun 2002, 03:08
Leading on from this... for any quad drivers out there. If you're 2 Engines out and past your committal point for the landing, and must go around, what sequence of actions would you execute?

Lancer

john_tullamarine
16th Jun 2002, 03:19
I suggest no different to the similar situation on one in a twin . . you land and do the best you can ... as the alternative to a much higher risk of dying ... especially if the two which are out are on the same side ....

One's commital point is just that ... else it would have been chosen to be lower the first time, surely ?

Checkboard
16th Jun 2002, 04:00
Four engine drivers unlucky enought to have two engines out, and with no other complications :), reduce weight to the two engine go-around performance weight if possibly (there is a table in the performance section of the FM) and approach with a reduced flap setting. Otherwise everything is pretty much similar.

*Lancer*
16th Jun 2002, 16:00
Valid points JT and Checkboard! :D

Asked the question as I have seen both a 2-engine (quad) and single-engine (twin) go around executed beyond the stated committal height successfully... While I'm not suggesting that you would consider doing something like that normally, but if you absolutely had to, would you have any idea what you would do?

The way it was demonstrated was to apply GA power and continue descending. One demonstration even involved retracting the landing gear while continuing the descent to reduce the drag and allow for rotation without the speed bleeding... Is the answer just a case, of 'do-whatever-you-can'?

Lancer

Checkboard
17th Jun 2002, 04:18
Two-engined ILS with a missed approach was a sim exercise for the BAe146 at Ansett.

john_tullamarine
17th Jun 2002, 05:34
One needs to consider what a "committal height" is and what it represents.

The hard deck decision height is what a rational flight test program determines for the conditions and is a bit like the H-V curves the helo guys get twitchy about ... serious stuff.... a missed approach from a lower level is most likely to be an underwhelming success ....

For normal operations, the operator will impose a comfort margin above the demonstrated figures, if they, indeed, exist, or, if not, the operator will determine some suitable comfortable level for its operations.

Either way .... either the pilot (operator) is serious in operations or not ... if one nominates a height then the whole idea of standard operations and rational behaviour goes out the window if we are going to try a missed approach from a lower height just because something untoward occurs.

In the situation of a for real two engine out (727 was in the same situation with two out ... only a bit worse off) ... then one would have declared a VERY serious emergency situation and there ought not to be many likely scenarios which could have the pilot comtemplating a below decision height missed approach.

... back to square one .... in such circumstances the pilot has to make a D ... better to try and avoid the errant obstacle and still land in the general area of the intended touchdown under control .. rather than land upside (Vmca departure) or with wheels up (during missed approach reconfiguring) ...

Could I enquire of Lancer what circumstances he/she envisages that would be so dreadful as to cause the pilot to contemplate sticking his/her neck in such a well-knotted noose ?

Re Checkers' comments ... sure, we all have done the exercise on 3- or 4-motored aircraft ... but to contemplate doing so in anger from a silly height is not very intelligent ...

*Lancer*
18th Jun 2002, 03:12
JT, one situation might involve an aircraft entering the runway about 1000 feet in when you're at about 150 feet... Of course, the situation is incredibly unlikely to occur, and there are a lot of 'what ifs', but some of the world's 'big' historical accidents were a result of the almost impossible eventuating and the crew dealing with it as best they can.

Regardless - you're right - it's not a noose you'd stick your neck in. Just thought I'd pose the question to see what people's ideas were!

Lancer

john_tullamarine
18th Jun 2002, 03:20
... of course, that is always on our mind .... the reason why one ought to declare a very serious level of emergency and dictate to the ATC folk what one's requirements are ... like making sure that everyone knows that there will not be a missed approach. ... etc

.. clearly there is no percentage in driving into the idiot who lined up ... the choices are ... miss if above the sensible minimum (plus a bit for the new clearance consideration), fly over the bandit (very hazardous), or do a sidestep and land on the grass ... none are palatable ... the management trick is to do everything practicable pre-approach to avoid such problems eventuating ..

411A
18th Jun 2002, 07:15
Hmm, well some of the "scenarios" presented here are only really interesting from the point of discussion....but if one absolutely had to, landing on any available parallel taxyway would certainly be an option...and certainly better that rolling inverted:rolleyes:

foxtrot
18th Jun 2002, 08:55
Eng1170 hye,
no matter what kind of a/c you fly it is always flaps and postive climb gear up, not only ground contact a issue but drag at that stage for when the wheel door open on selecting g/u you get the max amount of drag so you wait till the a/c shows postive climb and select g/u.
so it is TOGA or max thrust, nose up,go around flap,postive clm g/u.
take care, bye

mustafagander
18th Jun 2002, 11:30
A G/A in a 4 holer with 2 out on the same side requires the utmost care to ensure Vmca2 is achieved as quickly as possible.
As JT and others have said, I really think it could well be preferable to "land" on any bit of flat ground within the perimeter fence under control than fall out of the sky any old place out of control.
Commit height is just that.
In many cases a runway incursion is well survivable - how long is the tar, and how much do we REALLY need??