CRUISE flaps

I can't find a reference to anywhere --Pocket Guide, Chuck's Guide, NATOPS--, but I've been wondering, when I set flaps to cruise, their indicator still always shows 5°... always.

How do I get to 0°?

I think its always 5.

It has several settings. Cruise, Hover, etc. There's also an off switch position, or something to that effect. It will be at 0 then. Note : The flaps will not auto-adjust in this position, as they do in the others.

I think 5º is the actual AoA of the wing, so when the flaps are in line with the rest of the wing (cruise) they are at 5º.

If you set them at 0º they would act as ailerons.

As far as I'm aware, 5º is only used for super economic cruise, AAR and taxi (to avoid the flaps being reheated by the nozzles exhaust)

I think, that the optimal (least fuel consumption) will probably reached with 5° flaps and a specific speed (no idea). Thats why they are probably locked at 5° when in cruise.

IIRC the go to 0° when you set them to AUTO and are fast enough.

I can't find a reference to anywhere --Pocket Guide, Chuck's Guide, NATOPS--, but I've been wondering, when I set flaps to cruise, their indicator still always shows 5°... always.

 

How do I get to 0°?

TL;DR:

Flaps in Auto, airspeed above 0.95 IMN

Detail:

• Auto = 0° to 25°

• Cruise = 5° (flush with the wing profile)

• STOL = 25° to 62°

Flap angles are marked for the Harrier's old wing profile, the AV-8B's "new" wing is angled down and in normal flight, flap angle is 5° and flush with the wing profile.

Above 0.87 IMN, Auto is scheduled to progressively move from 5° to 0° flap.

Using Cruise mode (5° flap) above 0.87 IMN is prohibited.

The AV-8B's max airspeed is 585 KCAS / 1.0 IMN, so you are unlikely to see 0° flap, except when deliberately pushing the edge of the AV-8B's flight envelope.

A couple of pictures : https://forums.eagle.ru/showpost.php?p=3316683&postcount=33