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160knots
9th Dec 2016, 23:01
Hi
Does anybody know and can provide references to these questions please.
1. Does Icing effect VLS?
2. Apart from the 5 min and 10 min limitations on TOGA are there any other limits that need to be considered?
Engines are CFM56-5B4's

Thanks

RUMBEAR
9th Dec 2016, 23:28
1. This is not really a reference however the QRH Performance section includes VAPP determination. In this determination we make an allowance for ice accretion ( or not ). So it would be safe to say VLS assumes a clean airframe.

2. There are many engine limitations described in the FCOM Limitations section.

160knots
9th Dec 2016, 23:52
Thanks RUMBEAR.

The other limits I was referring to was specific to TOGA.

Thanks

RUMBEAR
10th Dec 2016, 00:24
In that case EGT limits. 950 deg or 915 for MCT. Or alternatively just worry when the EGT indication turns amber or red.

vilas
10th Dec 2016, 02:48
Icing increase the total drag on the aeroplane so the Vls increase. Even use of speed brake does the same.

Check Airman
10th Dec 2016, 07:47
How does your plane know if there's ice? Are ice detectors an option on the 320?

Uplinker
10th Dec 2016, 08:38
Don't know if they are an option or standard fit, but they are certainly available. I couldn't swear that all our 320/321/330 have ice detectors, but I am pretty sure they have.

We sometimes get the MEMO caption something like "Eng ant-ice on, no ice detected" (but the detectors can't see the cloud we are just about to fly into).

Check Airman
10th Dec 2016, 09:09
Ah. That makes sense. On airplanes with detectors, does the A/I come on automatically?

sonicbum
10th Dec 2016, 10:37
How does your plane know if there's ice?

Hopefully there are trained pilots aware of those conditions favourable for ice accretion that can manipulate engine and/or wing anti ice as required. The Airbus Dual Advisory Ice Detection System (DAIDS) is not intended to replace pilot's judgement but to support it.

Ah. That makes sense. On airplanes with detectors, does the A/I come on automatically?

Nope, we can still enjoy pressing the P/B.

vilas
10th Dec 2016, 14:51
Sorry! I didn't mean the aircraft knows icing and corrects Vls. The pilot's ensure it is kept ice free. But when anti ice is not available due engine fail fire push button pushed. There is 10 kts. addition to Vapp in icing conditions due to drag.

Fursty Ferret
10th Dec 2016, 19:09
The flight envelope protections assume ice build up. There's a photo somewhere showing them testing the 320 with huge blocks of foam stuck to the leading edge to simulate ice.

Check Airman
10th Dec 2016, 19:26
Sorry! I didn't mean the aircraft knows icing and corrects Vls. The pilot's ensure it is kept ice free. But when anti ice is not available due engine fail fire push button pushed. There is 10 kts. addition to Vapp in icing conditions due to drag.

That's how I read it. No worries. My last plane had detectors, and would adjust the speeds.

Check Airman
10th Dec 2016, 19:26
The flight envelope protections assume ice build up. There's a photo somewhere showing them testing the 320 with huge blocks of foam stuck to the leading edge to simulate ice.

Do you have a reference for that?

tubby linton
10th Dec 2016, 20:58
A320F Pro-Sup-30 Operations in Icing conditions refers.

Check Airman
10th Dec 2016, 21:04
Thanks for that.