India First week of monsoon

[vilas]

In the first week of monsoon there have been six incidents in last 24hrs by Airlines in India. Five were on B737-800 and one was on Q400. SpiceJet had three runway excursions on B737-800 and one on Q400 while AI Express on B737-800 had one excursion and one tail strike.

[vilas]

Can anyone one confirm that the runway excursion at Mumbai was due to a wheels up landing, as initial reports suggest so No it wasn't wheels up but runway excursion and nose wheel collapse. Rains have been torrential in Mumbai. Entire June rainfall took place in 48hrs.

[Sub Orbital]

Does landing on a contaminated runway ring a bell with anyone?

[krismiler]

All those fuel/oil/hydraulic fluid/rubber deposits accumulated on the runway during the dry season, washed up and mixed into a greasy mess by torrential rains. A bit like behind the line at a traffic light where cars stop in exactly the same spot and drip fluids whilst waiting for the light to change.

[Weapons Grade]

Does landing on a contaminated runway ring a bell with anyone?

I remember landing in VABB (BOM) - always used ABS MED or if runway damp, wet, VCSH or RESH, ABS MAX; and, full reverse thrust each time.

[DJ77]

I remember landing in VABB (BOM) - always used ABS MED or if runway damp, wet, VCSH or RESH, ABS MAX; and, full reverse thrust each time.

Reversers are OK, until your aircraft starts skidding. Then, they will not help you to restore control.

[Weapons Grade]

Oh, you mean skidding and diverging from center-line? I understand the use (or not) of thrust reversers in such a situation.
I was referring to braking action as a result of the runway surface at VABB

[ManaAdaSystem]

Maybe the indians should Google «grooved runway» and start doing something about their runways?

[The Old Swedish]

I remember landing in VABB (BOM) - always used ABS MED or if runway damp, wet, VCSH or RESH, ABS MAX; and, full reverse thrust each time.

Autobrake MAX. Seriously?

[zlin77]

Used MAX Autobrake reguarly into VABB on the 777 during Monsoon Season, why?..It looks better on the accident report (crew used all available means of retardation)..!!

[The Old Swedish]

Used MAX Autobrake reguarly into VABB on the 777 during Monsoon Season, why?..It looks better on the accident report (crew used all available means of retardation)..!!

Ok I did not know that Boeing allows MAX for landings. The bus doesnt allow you to use that, except for RTO obviously.

[Weapons Grade]

Autobrake MAX. Seriously?
You are quite correct - Airbus permits only auto brake MIN, MED or manual (and selection of MAX for TKOF only).
From memory, Boeing has ABS 1 thru 5; MD11 has ABS OFF, MIN, MED or MAX.
And as zlin77 stated (perhaps cynically) better to have maximum braking capability being used, than not.

[hans brinker]

I remember landing in VABB (BOM) - always used ABS MED or if runway damp, wet, VCSH or RESH, ABS MAX; and, full reverse thrust each time.

Max reverse sure, but if the runway length permits landing with Autobrake med in good braking conditions, then it won't help much to select Autobrake max with poor braking action (provided braking conditions are constant over the whole runway). Autobrake will give you a certain deceleration rate, if the wheels lack the traction to support that rate, nothing but more reverse or more runway will help.

[MENELAUS]

You are quite correct - Airbus permits only auto brake MIN, MED or manual (and selection of MAX for TKOF only).
From memory, Boeing has ABS 1 thru 5; MD11 has ABS OFF, MIN, MED or MAX.
And as zlin77 stated (perhaps cynically) better to have maximum braking capability being used, than not.

Not strictly true. Modern Airbi have BTV, with all the RCAM options, and brake max as a fallback.

[Flightmech]

You are quite correct - Airbus permits only auto brake MIN, MED or manual (and selection of MAX for TKOF only).
From memory, Boeing has ABS 1 thru 5; MD11 has ABS OFF, MIN, MED or MAX.
And as zlin77 stated (perhaps cynically) better to have maximum braking capability being used, than not.

MD11 has OFF, MIN, MED, MAX & RTO

[Cough]

Back to the thread... And following on from ManaAdaSystem's comment...

I'm personally very surprised that the native airlines haven't all got together to go and scream at each and every Airport Director (or even the AAI) for the runways to be grooved...

[arse]

https://theprint.in/india/big-questions-on-safety-pilot-training-after-5-indian-planes-veer-off-runway-in-3-days/257433/?fbclid=IwAR0Xo40f6m245Jk1jM2QzbkOXhdKtIYTxN1A0ddzMI6Wwd53Jd QAbnQNGrs

[gearlever]

"On Jul 3rd 2019 India's Civil Aviation Minister stated that due to Monsoon such occurrences occasionally happen as result of excessive rain, however, all is under control ..."

[Old King Coal]

Not so much something to with Training as the selection of suitable & capable candidates in the first place.

[FullWings]

I landed in BOM a couple of days ago and the runway seemed to be a bit grippier than I remember - has it been resurfaced? Anyway, I can confirm there was a lot of water about, three aircraft went around due w/s.

...it won't help much to select Autobrake max with poor braking action (provided braking conditions are constant over the whole runway)
I think the proviso rarely applies, as from my experience, the worse the braking action, the more variability there is. Water/slush/snow/ice is rarely evenly distributed and you’ve likely got areas of rubber deposits around the TDZ at either end.

Autobrakes generally go for a fixed deceleration rate on anything but MAX, where they function like the ABS on a car with your foot hard on the brake: they extract the maximum stopping performance available at that instant. Consider a runway where the braking action of 50% of the surface (not necessarily in one bit) is worse than reported and 50% is better - using MAX will get more stopping in the good bits and the same in the bad bits, so a net win over an AB setting that technically should give the same result but may surprise you on the day.

Downsides of using MAX AB? Err, maybe a little bit more brake wear? Downsides of going off the end...

[hans brinker]

I landed in BOM a couple of days ago and the runway seemed to be a bit grippier than I remember - has it been resurfaced? Anyway, I can confirm there was a lot of water about, three aircraft went around due w/s.


I think the proviso rarely applies, as from my experience, the worse the braking action, the more variability there is. Water/slush/snow/ice is rarely evenly distributed and you’ve likely got areas of rubber deposits around the TDZ at either end.

Autobrakes generally go for a fixed deceleration rate on anything but MAX, where they function like the ABS on a car with your foot hard on the brake: they extract the maximum stopping performance available at that instant. Consider a runway where the braking action of 50% of the surface (not necessarily in one bit) is worse than reported and 50% is better - using MAX will get more stopping in the good bits and the same in the bad bits, so a net win over an AB setting that technically should give the same result but may surprise you on the day.

Downsides of using MAX AB? Err, maybe a little bit more brake wear? Downsides of going off the end...

Agree mostly. On the A320 MAX is only for T/O. Don’t know enough about the B737, but landing performance on the A320 is better with full manual braking (like your car) than autobrake. Just the fact that there that many overruns suggests training/selection needs to change. Maybe less *have to get to the destination pressure?”

[ManaAdaSystem]

Really guys, you don’t know that different aircraft have different systems that work in different ways?
The NG has AB 1-2-3-Max for landing, RTO for takeoff.
Max can be used whenever it’s needed. Did that recently on a 1600 m runway and 63 T for landing. It uses a fixed retardation so more reverse give less brakes.
RTO is the full monty.
Landing runway 14 in BOM on a wet runway and 60+ tons LW you’ll be stupid not to use max.

[bill fly]

It was fitted to our DC 10 as a mod. Crews were informed by a memo from the fleet TP, with recommendation to use light or medium but not full, until experience was gained and a feedback form had to be completed each time.

Next scene - pre landing in HKG dry RW and quite light - FE says Autobrake? Capt on check says Oh - er Better use light - Check Pilot says Try Full - FE says I have to fill a form and it says Reason for use - Check Pilot says Put Inquisitiveness.

The landing - Touch down followed by the most brutal retardation I have ever experienced before or since - talk about being thrown against the harness - IAS falls like a stone - Check Pilot shouts Disconnect - Captain on check shouts How? I (probably the only one who had read the memo) say, Brakes. Captain brakes and the ship feels as though released from a bow. We are now at about 30 knots and have to use Fwd thrust to reach the first exit...

Taxy in with red faces, left side anyway and hot brakes - Capt makes an announcement about a new bit of kit - not working properly, sorry etc.
All good useful experience for the first officer.