How did the flaps work on the Hurricane MkIIc?
A recent discussion in IL2 forums regarding the action of Hurricane flaps gave me the curiosity. The problem seems that some literature states Hurricane flap deployment in two-stages, and I also thought that a UP/DOWN two-stage flap was normal in the Hurricane MkI and MkII.
But some people came up with the following article:
Air Ministry Air Publication 1564B & D, Pilot's notes for Hurricane II with Merlin engines
Ckeck List before take off:
Flaps up (28 degrees down - two divs. on indicator - for shortest take-off run.)
General Flying (iv):
In bad visibility near the ground, flaps should be lowered to about 40 degrees (3 divisions) and the propeller speed control set to give 2,650rpm.
Beam Approach:
Stage: Preliminary Approach, 1,500 ft alt, 120mph IAS (2400 rpm)
Actions: Flaps down 30 degrees.
Stage: At Outer Marker, 600ft alt, 95-100mph IAS (3000rpm)
ActionS: Flaps down 60 degrees.
Stage: Overshoot: Upto 400ft alt, 95-100mph IAS (3000rpm)
Actions: RAuse u/c and retrim, raise flap to 30 degrees and retrim. Raise flaps fully and retrim. Adjust boost and rpm at 1,000 ft.
So, it is confusing.
What exactly would a term 'two-stage' mean? Would it mean flaps were provided in only two possible stages? Or does the term 'stage' just depict a larger category of 'general settings', and intermittent settings between them possible..?
Another article I found about the Hurricane, was on the Hurricane MkI:
'Pilots Report - Hurricane P3351' by Keith Skilling
...The undercarriage and flap selector is the same lever, an H pattern operated in similar fashion to a car gear lever, and that in itself is a marvel of design or a masterpiece of confusion...
...The right hand is then used to release the gear safety latch and select first gear, on the gear/flap selector quadrant. This raises the undercarriage...
...First of all select second gear for undercarriage down, and then fourth gear for a few moments, for half flap...
...100 mph around base with half flap is comfortable, reducing to 95 with full flap crossing the fence...
This article seems to portray how the flaps worked, as a manual shifting gear system would work in a car. So from what I imagine:
1) there are four settings in the gear/flap box
2) gear1: raises flaps and landing gears to full shut
3) gear2: drops landing gears full down
4) gear3: initiates flap-down action, which, if left at gear3, the flap will drop down to its full position
5) gear4: momentarily 'locks' the flaps so it stops coming down. switching to gear3 again, will unlock it, and let the flaps down until it's fully down.
.. is this what I'm imagining correct? Would it work the same way on a Hurricane MkII?
..
If so, then why would they call it a 'two-stage' flap, when effectively it provides multi-stage capabilities?? Is there some disadvantage in this gear/flap single-lever system so that it should be differentiated with a 'multi-stage' system?
What are the limits of this gear/flap single-lever system, if any? From what it sounds like, wouldn't be actually be more efficient and precise way of controlling the flap degrees?
...
Wow, that's a lot of questions, so I'll number organize them and number them:
1) By what category do we call the Hurricane flap system? Two-stage, or multi-stage?
2) Did Hurri1 and Hurri2 have the same type of flap/gear single lever system?
3) Is my speculation above, about how this system works, correct?
4) What are the advantages and disadvantages of this system, particularly in its combat effectivity?
...
