Blip switch

[Hasse Wind 46]

Recently I've been flying rotary aircraft a lot, and have thought about that blip switch you can see just waiting to be pressed in the centre of the control column. As far as I know, there is no separate command for it in CFS3 (for obvious reasons), but would it be possible to have it in OFF some day? Is there any way it could be simulated with the controls we currently have, already in P3?

 

It would add some extra realism to flying the rotaries, and also improve their behaviour during combat. It's quicker to reduce power with the blip switch than with the throttle. And of course it would be historically accurate too.

[Olham 164]

As far as I understand, the blip switch switches between "throttle full" and "throttle idle" ?

In that case you can just set those two commands in "Controls" on buttons on your stick;

drop using the throttle slider, and use those two buttons instead.

[Hasse Wind 46]

Techinically speaking, the blip switch cuts off the ignition to the cylinders (at least to some of them), which allows extremely quick changes in engine speed, something that can't be done with the throttle alone, as far as I know.

 

The method you suggested, Olham, might work nicely if it's quick enough. Another possibility might be using the magneto switches, but that would mean having to push them repeatedly to shut down the engine and then start it again, and that wouldn't exactly be like a simple blip switch. But maybe something like that would work as a "blip switch simulation".

[Olham 164]

Restart with magneto would be much too slow, I think.

My method should work, as the throttle has many number steps inbetween "full" and "idle",

which you would all drop. It should be totally down at once, without the slider.

[Hasse Wind 46]

Yeah, you must be right. I'll have to test it the next time I fly a rotary aircraft. Thanks for the tip.

[Olham 164]

Even 10 % is not necessary my way, UncleAl. Throttle "idle" should be zero.

[Hasse Wind 46]

Hey, that might even better as it allows me to keep using the throttle slider normally. Thanks, Uncle Al.

 

Edit: Some rotary aircraft didn't even have throttles, so none of these methods are completely satisfactory for every situation. But for perfect realism, we need a separate command in the key configuration program.

Edited December 20, 2010 by Hasse Wind

[RAF_Louvert 101]

.

 

For sure uncleal, that is one way to do it. Another way, (and the method I use when flying the rotaries), is to map a pair of switches on the top of your JS to "SHIFT + M" and "CTRL + M". Click one and it shuts off the mags, click the other and it turns them back on. Works very well and you get much quicker response than with the throttle adjustments.

 

Cheers!

 

Lou

 

.

[Hasse Wind 46]

Okay, now I have bunch of methods to try. Thanks to you too, Lou. (That rhymes nicely!)

[RAF_Louvert 101]

.

 

Also HW, if you want to more accurately use throttle on the rotaries use the 10% - 50% - 100% keys, (1 -5 -0), rather than the slider. Most rotaries could cut out a portion of their cylinders to attain coarse "throttle" adjustments.

 

And you're a poet, and don't know it.

 

.

[Hasse Wind 46]

Haha, some poetry! Well, I'm not going to quit my job anytime soon. I have a feeling my rhymes are not enough to win the Nobel prize for literature, or any other prize for that matter.

 

Anyway, I'll start testing those blip switch settings now.

[Burning Beard 14]

I think I read somewhere that the actual blip switch was a little dangerous to use. You could cut the ignition but the fuel continued to flow because of the lack of and effective carburetor. If you left the ignition off for too long before restarting it cylinders could explode.

 

Beard

[RAF_Louvert 101]

.

 

You are quite right BB, and Bletchley offered an excellent outline of this some time back in the thread "A Question About Rotary Control". Here is his very informative entry:

 

 

"With the exception of the early Gnome rotaries (few of which were still in use by mid 1915), the blip-switch was supposed to be used only when the engine was already throttled back to idle - either on the ground, when taxiing, or in the air when throttled back for landing. The blip-switch was retained on all rotary engines because of the high idle speed of the rotary - most rotaries could not be throttled back much below 600 rpm on the ground or 800 rpm in the air. I have seen some evidence that the blip-switch was sometimes used in combat, but officially the use of the blip-switch at high engine speed was frowned upon because of the damage that it caused to the engine. Blipping the engine could also lead to flooding of the engine with excess fuel, which could lead to the engine cutting out for several seconds or even a fire under the cowling - not something modelled in OFF, but a powerful deterrent to use in combat. I model late rotary management in OFF by using the number keys across the top of the keyboard, using 6, 8 and 0 only (most WWI pilots had 'preset' positions of the throttle/fine adjustment for idle, cruise, and full power, and stuck to these), and only use the blip when throttled down to the '6' position. The mixture control can then be used for fine control of the engine speed, as well as altitude changes.

 

Bletchley"

 

 

 

IMHO, this is the best bit of info I've seen on the subject, and it offers a very historically accurate way of handling the throttle on the OFF rotaries.

 

Lou

 

.

[Bletchley 8]

I like to use the 'magneto' method of simulating the blip switch in OFF, described above by Lou. If you use this method to stop the magneto for too long (more than a couple of seconds) in OFF the engine will not restart again which, I think, simulates the flooding effect rather well :)

 

Although the first time you use it, you have to press the magneto-off key several times, you then only have to press the magneto-on once to restart the engine and then magneto-off and magneto-on once to stop and start the engine each time. I have the magneto-on and magneto-off key combinations asigned to 2 buttons on my joystick.

 

Bletchley

 

The best settings for idle-cruise-fullpower seem to vary slightly from one OFF aircraft to another, but I mostly use 4-7-0 or 4-8-0 - but trial and error will find a combination that suits, with the lowest key-number being the one that keeps the engine just turning over without dying, and the cruise setting being the one that will keep you up with the AI flightleader in level flight. In practice, historically, these were not preset positions on the throttle and fine adjustment quadrant - the pilot would have to find them for himself and remember them or mark the quadrant in some way:

 

"The engine has an rpm range from 800 to 1,150. It normally flies at full power but needs the 'idle' [control settings] for landing. The lever settings for take-off and approach must be memorized; these change with atmospheric pressure and temperature" (Neil Williams, Sopwith Pup pilot, quoted in L.F.E. Coombs 'Control in the sky: the evolution and history of the aircraft cockpit', Pen & Sword Aviation, 2005)

 

"To start up: fine adjustment about 1/4 of quadrant; throttle about 1/2 of quadrant. These positions cannot be given definitely as they vary on different machines but the right position can be found (Lt. R.T. Leighton, Sopwith Strutter pilot, 'Pilots' notes for the handling of World War I warplanes and their rotary engines', Shuttleworth Collection)

Edited December 21, 2010 by Bletchley

[RAF_Louvert 101]

.

 

More great info Bletchley, as always. And you kindly credit me in your post with that blip switch set-up I mentioned earlier on, but I am sure I adopted it from your numerous notes on the subject when I was first sorting out my OFF settings way back when. Give credit where credit is due, and in this case that would be to you good Sir.

 

.

[Hasse Wind 46]

Wow, blip switch information overload!

[RAF_Louvert 101]

.

 

Uncleal, I have a Logitech Extreme Pro 3D stick, and I have the mags on/off functions programmed to the two lower buttons on the top of the stick, while the mixture controls are programmed to the two bottom buttons on the base to the left of the stick, (once I have mixture set I don't tend to fiddle with it too much in combat which is why I located those controls on the JS base rather than on the stick itself). I set up "SHIFT + M" and "CTRL + M" as commands in the profiler and then assigned them to the aforementioned buttons. When I hold down the button assigned to "SHIFT + M" for about half-a-second it kills the engine, and holding down the other button assigned to "CTRL + M" for the same amount of time restarts it. This works because, (and I am assuming here), the Logitech software reads the holding down of the button as repeated requests for the same command. It dosen't seem to work the same way if you try to set it up as a keystroke assignment, but only as a command assignment.

 

Hope this helps.

 

Cheers!

 

Lou

 

.

[Bletchley 8]

Cutting off the fuel supply (either via the fine adjustment, or the fuel cock) was a recognized way to kill the engine for landing. As Uncleal says, this removed the danger of a fire under the cowling from any excess fuel vented from the exhaust valves. This is from Lt. Leighton's pilot notes (Sopwith Strutter, 110 hp Clerget):

 

"To land: shut off your engine. If above 500 ft turn your petrol off and leave switch [magneto] on. If at 500 ft turn petrol on and switch off. Coming down from a good height, try engine occasionally. Watch your pressure when engine is shut off"

 

(Avro 504K 100 hp Monosoupape) "To descend: shut petrol off...Although pressure is kept up by mechanical pump while engine is running, as soon as engine is shut off pressure must be kept up by hand...When about 50-100 ft from the ground put petrol lever to one inch and hold thumb switch down but do not 'buzz' engine...Taxi in by 'buzzing' engine with petrol about 1 inch on adjustment...Before getting out of machine put switch and petrol both off and let pressure out of tank by opening release valve at bottom of pressure pump"

 

Bletchley