Author Topic: OPPS!!! OUTA GAS? HOW'D THAT HAPPEN? Gliding simplified!!!!  (Read 995 times)

Offline DamnedRen

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OPPS!!! OUTA GAS? HOW'D THAT HAPPEN? Gliding simplified!!!!
« on: November 08, 2003, 05:28:39 PM »
I posted "landing? simplified" a while back and saw a post from xtinct concerning "gliding and landing without the crashing part" so I thought I'd touch on getting home when you've overstayed your welcome at an enemy field and you're almost on empty.

To start with let me be the first to say I HAVE hung around at a field dogfighting and havin a grand old time only to notice that 1/8  tank of gas just isn't gonna get me home unless I can come up with miracle. Well, miracles can happen. Here's how.

Disclaimer: Im not gonna go into the intricate details of l/d, etc but I am going to give you what  folks in the flying industry call a "gouge".
A gouge can be anything from a fuel flow rate (to maintain a given airspeed) to glide ratios (ah, the point of this post).

Ok, lets begin with the MAP (clipboard). Everyone knows each sector (square) is 25 X 25 miles. Armed with that knowledge the first gouge is you can make a quick determination of just how far "home" is. Right? Half way across the sector from where you are now is "home". Ok, that's easy! Im about 12 miles from home!!!

So let's use that 12 miles as a known distance home. Now let's talk about the planes. Pick one. it doesn't matter. Hopefully, it's one you like flying alot! Perhaps it's one that you think glides like a brick. Are you sure? Anyone ever see "12 oclock high" or maybe the "Memphis Belle" movies? You notice when they lose an engine they "feather the prop"? What they are doing is turn the blades so they align with the wind instead of produce alot of drag. It's the same as you riding in the car when you were young. You'd stick your hand out of the window and feel the wind over it. If you went "knife edge" it cut through the wind. If you turned your palm into the wind you would feel it hitting and pushing against your hand. Right? Well, that's exactly the same effect that a propeller has in the air. Ok, so far we know if we feather the prop it reduces drag. Reduced drag? Kewl!!! If you have less drag you extend you glide!!! Simple, huh? Well, just like the B-17's of WW2 you can feather your prop. All you do is hit your - (minus) key and you will see your RPM's drop. Why? The wind hitting your prop is causing it to windmill or turn. This windmill increases drag considerably. Higher drag = lousy glide ratio.

Ok, we know we can increase our glide by hitting the minus key until the rpms drop. That's great but how do I know I can get home even if I can glide a little farther? Well, it's very simple and you can use the following as a gouge to get your home.

To review:
we're 12 miles from home.
We can increase our glide.

But how do we know how far we can glide? It's simple!!!

You can "plan" on gliding most AH fighters a distance of 1 mile for every thousand feet of altitude you have in a clean (feathered prop) configuration. Simple, right?

Lessee, 12 miles from home, got an 1/8 tank of gas left. I'm currently at 6k alt. I really need to do a couple of things, FAST!!!
1) turn for home (every mile you fly towards home makes the glide alt lower)
2) Grab like crazy, you need 12k to go 12 miles, but you only need 11k to go 11 miles. You are flying toward home, right?
3) As soon as you hit the magic alt hit x key and go level. Yes, you can use the auto pilot features to help you fly. In fact, many major airlines want you to use autopilot for most of the flight.
4) Ok, you hit x, now cut the engine. Don't waste any more gas while in the glide.
5) Hit MINUS key til rpm's drop as far as they will go.
6) As the speed decays to about 120 mph, go off autopilot level and let the nose drop to 1000 feet
descent rate. Once you hit 1000 feet per minute (FPM) hit shift x and go to auto pilot "angle". Guess what? The autopilot will hold your plane in that 1k fpm down angle. Simple, huh?
7) Kick back, grab a drink, use the head,look for
enemy fighters trying to hit you, whatever.
8) As you near the field you can adjust your rate of descent (decay? ) by unfeathering the prop a little. Hit the plus (+) key as needed to shorten your glider for landing. Remember, you can add or take away drag at anytime. Simple, right?
9) As you come over the numbers, hit flaps then gear and just feather the prop a little and your plane will extend its glide along the runway. This will act like ground effect and slow its descent to the runway. Add a little back pressure and she will settle on the runway in a three point landing (if you're flying a tail dragger). Simple.
Or, just turn on the engine and use it to land. Remember, you may still have some gas left?

Alright, here's the gouge listed.
1) Determine your distance to home and turn for it.
2) Grab to glide alt
3) Hit X and cut engine (e key)
4) Feather the prop (- key)
5) Let the plane slow then nose over to 1k fpm down and hit auto angle (shift x)
6) Kick back for the glide
7) Feather and unfeather (- and + keys) as needed once at field to get her down to a landing (don't land short)
8) Over the numbers use flaps and gear as a brake.
Remember them?
9) Alternatively, restart the engine and land

Simple!!!

Ren

Offline Zaphod

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OPPS!!! OUTA GAS? HOW'D THAT HAPPEN? Gliding simplified!!!!
« Reply #1 on: November 08, 2003, 06:34:35 PM »
Great advice,

One thing to add....you can also conserve fuel while flying level by reducing prop rpm's to the lowest it will allow (hold the minus key until the rpms stop going down) then reduce throttle to about 3/4's or 2/3's max.  This will allow a pretty decent level speed while significantly reducing your fuel consumption.  So you can grab to a reasonable alt, then once there get level and build some speed then reduce rpms and throttle.  I usually use my fuel gauge as a guide as to when i stop grabbing.  If I'm worried that I won't make it I will grab until I have about 1/8 tank left, then get level and build speed to close to max. for that alt then reduce rpms and throttle.

You can also use the Alt X command coupled with the .speed command to control your glide flight.  Set your speed to 120 or so (.speed 120) then hit alt x.  The autopilot will set the glide slope to meet 120 mph.

Whichever method you use (alt x, shift x) know that using the autopilot will generally fly the plane more efficiently than you can flying it manually, thereby increasing the amount of time you can remain in the air while gliding.

Zaphod

Offline Seeker

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dweeby buff landings.....
« Reply #2 on: November 09, 2003, 05:24:51 AM »
Alt-X is auto speed, not auto climb, as many think. The plane will alter pitch (climb or dive) to hold the speed you set with the dot speed command.

So......

set speed to be 120;

Jump to nose gun;

Control climb/dive with throttle; and you can land from the nose gun with a perfect view.

:)

Offline Blue Mako

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OPPS!!! OUTA GAS? HOW'D THAT HAPPEN? Gliding simplified!!!!
« Reply #3 on: November 09, 2003, 07:32:22 PM »
Ren you are spot on about everything except the speed to use.

Without delving into the physics too deeply, in most airplanes the best glide ratio is attained at the speed for best L/D ratio.  This is also the speed for best climb rate, which is (conveniently) the default speed set by HTC for the alt-x command for each plane (give or take a few knots caused by altitude variation).  The best glide angle speed, which will take you farthest, is higher than the speed for lowest descent rate so don't think that just because your descent rate and forward speed is high that you won't go as far, you will in fact go a lot further.

Try it, you will find that you will glide a lot further by using the alt-x (maintain speed) command on default settings.

The steps for best glide distance are:

1. Grab as high as you can using alt-x on default speed and full throttle.

2. Shut the engine off while you still have a little bit of fuel, save it for last minute approach maneuvering.

3. Reduce the prop RPM as much as possible using the - key.

4. Leave the airplane to glide on the default alt-x setting.  Do not use auto angle or try to reduce the rate of descent by slowing down, this will only make you fall short of your field.

Using this method I can glide 2 or more miles for every 1,000ft of altitude in my mustang.  It's best glide speed is about 175 indicated.  If I tried to glide it at 120 I would only get about half the distance.

:cool:

Offline Gooss

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OPPS!!! OUTA GAS? HOW'D THAT HAPPEN? Gliding simplified!!!!
« Reply #4 on: November 10, 2003, 08:39:43 AM »
Thanks, Ren.  Nice write up.  Good information.
CHICKS DIG GULLWINGS
flying and dying since Tour 19

Offline DamnedRen

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OPPS!!! OUTA GAS? HOW'D THAT HAPPEN? Gliding simplified!!!!
« Reply #5 on: November 10, 2003, 02:11:26 PM »
Yer welcome Gooss:)

All the other responses are great also!

I think the idea I want to get across is that many, many times you CAN get back home.  Just make sure you a plan in the back of your mind when the alarm bells start going off.

Also, remember you may have a portable airfield nearby. A CV will take just about any plane AH has to offer. If you have 4-5 kills and the engine starts sputtering for lack of gas a CV may be just the thing.

Regarding CV's... if you happen to be driving one, please look after yer fellow pilots. If you keep changing course when its not necessary and compound their problems with a turning deck then you're not helping anyone. The guy you help take aboard today might be the same guy who's driving the CV tomorrow when you're in trouble and need a place to put down.

Ren

If anyone wants "CV Landing Simplified" I'll knock one out. It's is simple if you can see and use the clues around you.

Offline Marco50

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Fuel~
« Reply #6 on: November 10, 2003, 02:22:35 PM »
Two buttons can make all the difference to bring in fueling :)

(Shift-F) ~~~ Oh and hi Seeker!

Offline xtinct

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OPPS!!! OUTA GAS? HOW'D THAT HAPPEN? Gliding simplified!!!!
« Reply #7 on: November 12, 2003, 07:16:04 AM »
Thanks for all that valuable advice! Didn't know about the feathering thingy ;-). Still got one more question concerning landing without the option to restart the engine (damaged or out of fuel): Could it be that the brakes don't work properly when the engine is out? I'm quite often able to land (i.e. SpitV with approx. 120 speed) but then cant bring her to halt and overshoot  / crash having brakes pulled all the time. Any idea?

cheers

xstinct

Offline DamnedRen

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OPPS!!! OUTA GAS? HOW'D THAT HAPPEN? Gliding simplified!!!!
« Reply #8 on: November 12, 2003, 08:27:16 AM »
Is the mph landing speed with flaps up or down? If your speed is high the plane can float a long way down the runway.

Flaps adjust the nose attitude. They have a tendency to lower the nose which provides lift with the added benefit of being able to peer over the top of the cowl and see the runway. Flaps also greatly increase drag. This means if you have a running engine and you wish to maintain the desired descent rate you will find you need to add power. And, with flaps extended  you may find your actual stall at touch down speed is 80 mph. That makes a difference of 40 mph, as noted by your saying you come over the numbers at 120 mph.

So, a suggestion if you are forced to land with your engine off;
1) Remember the feathering of the prop? You can also add rpm. This will increase the drag and slow you down. The keys are + and -
2) Get your flaps down. q=down, w=up
3) As you line up for the approach aim your planes nose at a point about 200 feet down the runway.
4) Save your gear for last. Make sure you have the runway made at a nice slow speed (100 mph or less) then get your gear down. If you misjudged your altitude on final and find you are high then get the gear out early as it will add more drag and allow you to remain slow as you get the nose down to make the near runway end.
5) Look down at the far end of the runway for alignment. The farther down you look the more accurate and minor your runway alignment adjustments.

A good way to practice is to take off head out and grab some. Turn inbound and cut the engine. Get your plane dirty and practice a few engine off landings. If you run into trouble hit the old e key and go around and try again.

Hope this helps.

Ren

Offline Ghosth

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OPPS!!! OUTA GAS? HOW'D THAT HAPPEN? Gliding simplified!!!!
« Reply #9 on: November 12, 2003, 08:29:49 AM »
Props turning at idle actually have a brakeing effect.  So deadstick landings tend to be tricky without it.

Try to get a little slower on approach, I also try to save 15 seconds of fuel if at all possible. Enough for a bit of boost if needed.

Brakes do work but they are being pushed to work twice as hard.

Offline xtinct

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OPPS!!! OUTA GAS? HOW'D THAT HAPPEN? Gliding simplified!!!!
« Reply #10 on: November 12, 2003, 08:41:51 AM »
Thanks for your advice - I normally try landing w/ full flaps and gear out as soon as speed allows it. But from what I gathered I might have been just too fast for the limited brake capacities.

cheers
xstinct