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-   -   Balked landing Boeings (https://www.pprune.org/tech-log/648501-balked-landing-boeings.html)

vilas 23rd Aug 2022 15:20

Balked landing Boeings
 
Balked landing 737 max or B777 procedure, when are the flaps one step retracted? Ensuring climb or straight away like normal go around?

exeng 23rd Aug 2022 16:46

On the 737 the call is (or certainly was) 'go around flap 15' (from normal land flap position 30, or 40), simultaneously one press of the toga switches to give reduced go-around power; or press twice if you want to get really excited! If a non normal flap 15 landing, then it was as above but the call was 'go- around flap 1'.


Years since I've flown the 777, but I believe it was the same.


kind regards
Exeng

FullWings 23rd Aug 2022 19:32

On the 777 you get it into the air with the config warning going, get it settled in the climb, then actions as per normal GA like exeng says.

esreverlluf 24th Aug 2022 02:34

Retracting "one step" of flap for a go around is more of an Airbus thing . . . Boeing airliners will have a particular flap setting (15 or 20 depending on the type) for a normal go around.

vilas 24th Aug 2022 06:42

Actually it's not Airbus or Boeing thing but aerodynamics of ground effect comes in play which is same for both. In ground effect the wing is more efficient and CL Max, so is stalling AoA is reached at lesser AoA than when outside ground effect. The thrust may be idle and aircraft path downwards. When you go around from here AC transits out of ground effect the thrust is coming up, speed may be lower than Vref and aircraft sinking. Raising flap will add to this deficiency. If you raise AoA it may reach stall AoA. Air Canada 646 stalled and was destroyed. G650 crash on takeoff killed two test pilots. I want some expert views in this.

Jwscud 24th Aug 2022 08:15

The G550 flight test crash was on rotation while trying to meet flight test objectives so while it is ground effect related (iirc the ground effect on stalling AoA had been miscalculated) it doesn’t have much relevance to discussion on balked landing or go arounds. I’m afraid I’m absolutely not an expert, just a line pilot but this is what I can share

I recall a training presentation stating that the Vref for landing flap on Boeing aircraft was the same speed as V2 for the go around flap setting, providing the same stall margin. I’m afraid I no longer have access to my 777/737 manuals and training department policies changed as to how balked landing should be flown but the most recent I recall similarly delayed flap retraction until the aircraft was airborne.

Differences in philosophy as to how to enter the go around mode also led to differences in thrust lever handling which necessarily changed the initial flight crew focus. The TOGA switch inhibition close to the ground on the 777 led to a need initially to disconnect the auto throttle and apply thrust manually.

vilas 24th Aug 2022 14:27

Jwscud
even on takeoff same situation exists. There's another accident that happened in India in 1977 on B737 200. When takeoff flap was selected the leading flap didn't extend. That time there was no indication/warning for leading edge flap. So the rotation speed by default became inadequate. At VR the aircraft got airborne in ground effect but was unable to climb out of it. It crashed at the end of the RW killing some workers on ground and aircraft was written off. If flap is retracted in GA at 50ft before established in flight path, thrust and speed it will have the same effect.

john_tullamarine 25th Aug 2022 01:49

A lot changed progressively with the introduction of the PAMC report on performance. Very few of us still flying who date back to that time .... early 50s (?) or thereabouts - I should look it up but it is not conveniently to hand just at the moment.

Another related consideration involves the possibility of an engine failure.

For the landing we consider two configuration cases - approach (gear up, approach flap and OEI) and landing (gear down, landing flap, AEO). For the wave off, there is little benefit to be had (once the aircraft is climbing) in maintaining the landing configuration. Consequently, the typical process is to select approach flap and go around thrust, wait/check for a positive rate and then select gear up. Now, you will be doing far better compared to the landing configuration miss and, you also have some protection for an engine failure during the process. In earlier times, initiating the miss from a landing configuration OEI approach would have to qualify as one of the harder stick and rudder tasks for the pilot .... if, indeed, feasibly achievable.

Generally, speaking, a wave off in the landing configuration, with an engine failure, is not going to end well.

One mishap with good consequences for the folks on board, if not for the hull, and rather near to home for us Ozzies - Ansett F27 Crash @ LST in 1965 - PPRuNe Forums

FlightDetent 25th Aug 2022 03:11

Is the OP asking about a published (or not) OEM guidance?

vilas 25th Aug 2022 03:38


Originally Posted by FlightDetent (Post 11284706)
Is the OP asking about a published (or not) OEM guidance?

The issue is of go around near the ground where aircraft transits from in ground effect to outside ground effect. A320 FCTM clearly states "Only when the aircraft is safely established in go around the flight crew retracts flap one step and the landing gear". Since the situation is same for even Boeings I wanted to know their philosophy and recommended procedure.

FlyingStone 25th Aug 2022 04:44

From the 737 FCTM:


When performing a balked landing, disengage the autopilot, disconnect the autothrottle, smoothly advance thrust levers to go-around thrust, and verify speedbrakes are retracted. Maintain landing flaps configuration and smoothly rotate toward 15° pitch attitude at no less than VREF. Column forces during rotation can vary. When safely airborne with a positive rate of climb, continue the Go-Around and Missed Approach procedure as prescribed in the FCOM/QRH.

WARNING: After reverse thrust is initiated, a full stop landing must be made. If an engine stays in reverse, safe flight is not possible.

Note: The takeoff configuration warning horn sounds when on the ground due to landing flap configuration.

Selecting the go-around flaps during a balked landing can cause a decrease in the airplane lift and can result in increased takeoff distance. However, if there is sufficient runway remaining to safely complete the balked landing with the go-around flap setting, the go-around flap setting can be selected.

vilas 25th Aug 2022 06:56


Originally Posted by FlyingStone (Post 11284721)
From the 737 FCTM:

Thanks. I just laid my hands on the 737 FCTM. Boeing seems to make distinction between GA before touchdown as a rejected landing and at touchdown or after touchdown as balked landing. Before touchdown they don't forbid retraction of flap and seem to recommend normal go around. Only after touchdown they don't recommend retraction of flap immediately but that too for reason of takeoff distance availability if yes then normal go around. A bit strange but they know better.

Goldenrivett 25th Aug 2022 07:17

TOGA 10
 
Hi Villas, for the last 15+ years we’ve had a “Toga 10” procedure for a baulked landing where we set the TL to TOGA and limited the pitch rotation to 10 degrees. In the simulator the aircraft would sometimes settle onto the runway for a second or two until the engines produced the power and the aircraft accelerated before lifting off. Once airborne, we’d call “Go Around - flaps” and only then reconfigure during a normal GA procedure.

Denti 25th Aug 2022 07:56

TOGA 10 is not an official Airbus procedure. Using that on the A321 can cause a tail strike. I suspect for that reason it has been renamed in the FCTM to „Go-around near the ground“, at least in the version i have access to.

vilas 25th Aug 2022 08:22

Although TOGA TEN is not official, for A320 I am aware some Airlines using this term. A320 FCTM wording is to avoid excessive rotation rate.

Cough 25th Aug 2022 13:29

There is a 787 BAB issued (similar to an Airbus OEB) which describes a balked landing. Flaps to be retracted once climbing away.

vilas 26th Aug 2022 06:12


Originally Posted by Cough (Post 11285022)
There is a 787 BAB issued (similar to an Airbus OEB) which describes a balked landing. Flaps to be retracted once climbing away.

Can you quote it? Also full form of BAB?

Cough 26th Aug 2022 16:32


Originally Posted by vilas (Post 11285400)
Can you quote it? Also full form of BAB?

In a nutshell I can't paste company manuals here... It's BAB 65 if you can get that. It's almost word for word from the 737 FCTM as quoted by flying stone with the addition of the line that once airborne push the toga switch (A/T activation, F/D guidance activates). After that, once safely climbing away continue with the normal go around procedure in the FCOM (retract flaps etc...)


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