Friday, August 4, 2023

Aborted landing / Balked landing - a recent experience



We were scheduled to fly from Bengaluru to Goa and were to depart

from terminal 2 of KIA Bengaluru. We were there well in advance,

spent some time looking around the splendor of the new terminal,

experienced whatever the lounge had to offer and boarded the flight.

The pre-departure experience was fine. 


The flight took off from Bengaluru on time. I read for some time and dozed

for about half an hour. After some time, I experienced some turbulence

and realised that we were in the clouds and were on our way down.

Looking out of the window, I saw the mining pits of Sanvordem, the

roof of MRF and Nestle, the Verna industrial estate, the new six lane

highway crossing the river Zuari and then the BITS Goa campus located

close to the airport. 


The captain made an announcement and the flight started the steep descent.

It crossed the Zuari industries and the highway, past the Airport fence and

touched down with a strong bump. It seemed to raise a bit, appeared to

have made a second touch and instead of slowing down, gained speed

again! Even before I could realise what was happening, we were airborne

once more.


I knew there was something wrong and that it was serious. There were

butterflies in my stomach. But when I found that the aircraft was stable

and steadily gaining height, I calmed down and after noticing that it was

banking and had started making a U turn, I felt that things should be OK.

But there is no escaping the fact that all of us had been very close to our

last few seconds on this planet.  I don’t think many of my co-passengers

realised that a disaster had just been averted.  


In retrospect, I feel that the plane touched down with more speed than

usual. Maybe the pilots noticed that they would be short of the runway

and decided to take off, instead of trying to stop and overshooting the

runway. It is also possible that they experienced a sudden gush of cross

wind and decided to take off instead of veering away from the runway.

These are my guesses. I enquired with the cabin crew after landing but

they had just as much information as I did. 


I dont know whether I should thank the Pilots or my fate. But I am glad

that I am back in my home and typing this. I am curious to know what

exactly happened. If I get to know, I will come back with details. Meanwhile,

I felt like sharing this unusual experience and hence, you are reading this.

Bye.


I sent the above write up to a friend, who is an experienced pilot and

got the following 

response. 


Response : As for my view on the experience,


It is a little difficult to be sure about what might have happened without

actually being in the cockpit or speaking to someone who was in the cockpit

at the time. My best guess would be same as your father's first assumption. 


1. They may have come in too high on the final approach and as a result

touched down out of the ideal touchdown zone (roughly the first 25%) on the

the runway. When that happens there may not be enough runway to stop the

aircraft and the aircraft can go off the runway which can be disastrous. In this

situation, it seems like the cockpit crew realised this and aborted the landing

and carried out a Go Around maneuver (a maneuver where the landing is

aborted on final approach or after touchdown and the aircraft climbs to a certain

height and attempts another landing or diverts to another field)


2. They may have come in at the correct height but may have been too fast

and resulted in the same outcome of touchdown towards the mid or second

half of the runway and eventually carried out a go around.

3. Could be a combination of 1. and 2. Resulting in a go around.


I think the crosswind explanation is possible but less likely because Goa is

not one of the airfields where crosswind is a major concern.


What happened here is technically called a balked landing. Where a landing

is rejected very close to the ground or sometimes even after touchdown.

The engines are producing very little power when coming for landing and

close to the ground. From this state for the engines to start producing

maximum power in order to start climbing again it takes a few seconds.

This lag for the engines to go from low power state to max power is due

to design. And it is this lag in the power delivery of the engines is what c

aused the second touchdown. Momentum would have carried the aircraft

in the air after the first touchdown and lag in power delivery caused the

aircraft to sink and cause the second touchdown and as the engines reach

max power the aircraft will have started climbing again.


Ideally this landing should have been aborted at a much earlier stage.

It is extremely unlikely if the aircraft is on the correct height profile and speed

on final approach to end up in this situation. However, they did have the

good sense to do the right thing albeit at the very last stage.


I know my reply is very long and detailed 😂. But I wanted to explain

certain concepts so that he will understand the explanation better.

I hope this helps.








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