A320 Dual HYD

[MD83FO]

One year off the line getting a bit rusty, query regarding Vapp with loss of G + Y, Vapp = Vref + 25.
what will be my VLS margin? how close can i get to VLS with the aim to reduce energy over threshold.

thank you.

[Field In Sight]

VREF means Vls when in config FULL. i.e. Vs + 30% margin. (1.23 x Vs1g in Airbus speak).

Therefore if you did a flap full landing your margin over Vls would be zero if you didn't add any approach correction.

The same applies for abnormal configs i.e.
Vls = Vs(current config) + 30% which happens to be VREF + 25kts for G+Y failure.

So you only have a margin over it if you need to add an approach correction or decide to increase your Vapp speed for turbulence etc.

At our lot, we always add at least 5kts and never fly Vls, even if using manual thrust due to risk of tailstrike.

Hope that helps (and is correct, it's late).

[vilas]

MD83FO
In this case you actually fly the VLS all the way. There is no approach correction beyond 20KT. So there is no question of any energy reduction. You are perhaps comparing it with overweight landing procedure where you fly the normal addition to VLS till 200ft or so and then reduce to VLS to reduce energy.

[MD83FO]

Thank you vilas, do we need to reffer to the landing with flaps or slats jammed? Or does the summary suffice.

[sierra_mike]

the summary takes care of it

[vilas]

MD83FO
Summaries are created for four serious abnormalities(three dual hydraulics and EMER ELEC config) to give different procedures like landing with slat/flap jam, landing gear gravity extension in one place. You may have to refer to slat/flap jam for determination of MAX speed for GA. It can also be determined from VFE given above ISIS.