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Black Pudding
25th Jan 2019, 19:30
Many years ago, I used to fly 737-800s for a UK tour operator. We had a recommendation that we did not tanker fuel to land above 5400 kgs (2700 kgs each wing) as there was a chance of a cold soaking effect, meaning a possible need to de ice. Does anyone use similar procedures or recommendations for your aircraft type particularly the A320 which is what I now operate.

Jonty
25th Jan 2019, 20:20
Yep, don’t land with more than 6000kgs if the flying time is greater than an hour. It’s not a limitation, and I think any reference to it has been removed from the fcoms. However, it’s still in our company manuals as advice.

fantom
25th Jan 2019, 21:02
What about when you are tanking? Never had this problem mentioned.

Jonty
25th Jan 2019, 21:35
This is the actual section from the manual:

Ice accumulation due cold soak.
Should the Commander​ consider that this​ may​ be a​ factor​ when considering​ the duration of​ ​
the flight and ambient conditions, the​ following​ guidelines​ are recommendations​ to avoid​ ​
this​ possibility.​ Recommended landing​ fuel​ to avoid cold soaked induced ​ icing:

A321 6000kgs

Its not a limitation, it’s a recommendation.

lomapaseo
26th Jan 2019, 03:28
Many years ago, I used to fly 737-800s for a UK tour operator. We had a recommendation that we did not tanker fuel to land above 5400 kgs (2700 kgs each wing) as there was a chance of a cold soaking effect, meaning a possible need to de ice. Does anyone use similar procedures or recommendations for your aircraft type particularly the A320 which is what I now operate.

I don't believe it's an inflight issue while tankering, but more an issue having to do with dispatch after having arrived while tankering.

I am not aware of a safety issue during the inflight phase (probably due to the rarity of encountering water particles etc and the formation of the resulting thin ice on non-critical surfaces including self-sheddings at high airspeeds)

However should one encounter near freezing icing conditions on-the-ground The cold soaked fuel may affect dispatch of the flight and will probably result in a larger sheds during rotation.
All this can be countered by requring a more diligent inspection for ice on a tankering aircraft if near freezing conditions exist at that airport at the time..

THRILLSEEKER
26th Jan 2019, 07:50
To minimise the chance of the dreaded ice T on the 320 it’s best to land with no more than 5000kgs ... I try and keep it to 4.5T max on landing.

Even that doesn’t work everyime, it depends on the environmentals.

TS

compressor stall
26th Jan 2019, 09:45
Even that doesn’t work everyime, it depends on the environmentals.

And the reverse. I fly regularly to well below zero environments landing with ~16T (departing with ACTs full and landing with return fuel for a 5 hour trip home) and have no issues, as the air at destination is so dry.

airseb
26th Jan 2019, 12:24
The problem is for a long flight with the fuel in the wings becoming very subzeo. You can then land in even tropical conditions and have ice on the top of the wings. And certain places have no deicing. So you vave to wait for the fuel to become positive or the sun to shine. I fly the T7 and landing with more than 20 tonnes in a tropical country would put you in the above case. (And imagine deicing in HAV or BZV...)

FlightDetent
26th Jan 2019, 13:05
5000 too, empirically determined at the last Co.