Author Topic: Flight Sim  (Read 19619 times)

Offline Frank N. O.

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Re: Flight Sim
« Reply #30 on: March 28, 2006, 10:51:45 PM »
Btw I was wondering, how much can you move a real plane's controls? (sorry fi I asked this before I can't quite remember).
One particular interest is also the pedals, how heavy are they? Are they like pushing down on the clutch of a sportscar or more like the throttle-pedal? And if it's light then could it work to design hanging pedals a bit like the throttle on a car for a more relaxing seating-position (wheel-brakes would be placed seperately, possibly as seperate pedals between the rudder-pedals).

And speaking of brakes, how does a plane handle on the ground? In MSFS it's like skidding on soap, one wrong flex of the rudder and the plane goes into what I think is called a Ground Loop (spin around like a car with locked rear-wheels at forward momentum).

And speaking of brakes, how fast can a small GA plane stop anyway? I assume that the lift of the wings are a factor even under stall-speed but can that be helped by pushing forward a bit on the yoke, or retracting flaps to reduce lift and thus put more weight on the main wheels to improve grip?

Edit: Flyingblind I'm actually danish, men jag kan pratta en del svenska og selvklart forstå det da dansk och svensk are beslektade språk i motsætning til norsk (that last part was attempted swedish, swedes and danes, and norwegians can mostly talk to each other on native languages since they're closely related, kind of a bond that I don't think many other countries in the world share). I normally call myself scandinavian instead of european since it fits more precisely culturally although even in Denmark I'm an excentric and don't really follow any normal class-type behavioural patterns, but that's mostly only in a good way. Btw, that you said sounded or at least looked more like finnish that I believe is related to the languages in your area isn't it? (I got that from a finn) People say danish sounds most like norwegian but in reality danish is related to swedish where norwegian is from the other branch of scandinavian languages, I think the difference is the accent, if you ever hear a dane speak english then there's a big difference in the fullness, or rather lack of, in the accent from a dane vs a swede, and norwegians they sound like they're singing, rhythm. Incidentally, icelandic is said to be very close to the orignal common language spoken during the viking-era.

Frank
« Last Edit: March 28, 2006, 10:55:27 PM by Frank N. O. »
"When once you have tasted flight, you will forever walk the earth with your eyes turned skyward, for there you have been, and there you will always long to return."
— Leonardo da Vinci

Offline Ted_Stryker

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Re: Flight Sim
« Reply #31 on: March 28, 2006, 11:10:36 PM »
Btw I was wondering, how much can you move a real plane's controls? (sorry fi I asked this before I can't quite remember).
One particular interest is also the pedals, how heavy are they? Are they like pushing down on the clutch of a sportscar or more like the throttle-pedal? And if it's light then could it work to design hanging pedals a bit like the throttle on a car for a more relaxing seating-position (wheel-brakes would be placed seperately, possibly as seperate pedals between the rudder-pedals).

And speaking of brakes, how does a plane handle on the ground? In MSFS it's like skidding on soap, one wrong flex of the rudder and the plane goes into what I think is called a Ground Loop (spin around like a car with locked rear-wheels at forward momentum).

And speaking of brakes, how fast can a small GA plane stop anyway? I assume that the lift of the wings are a factor even under stall-speed but can that be helped by pushing forward a bit on the yoke, or retracting flaps to reduce lift and thus put more weight on the main wheels to improve grip?

Edit: Flyingblind I'm actually danish, men jag kan pratta en del svenska og selvklart forstå det da dansk och svensk are beslektade språk i motsætning til norsk (that last part was attempted swedish, swedes and danes, and norwegians can mostly talk to each other on native languages since they're closely related, kind of a bond that I don't think many other countries in the world share). I normally call myself scandinavian instead of european since it fits more precisely culturally although even in Denmark I'm an excentric and don't really follow any normal class-type behavioural patterns, but that's mostly only in a good way. Btw, that you said sounded or at least looked more like finnish that I believe is related to the languages in your area isn't it? (I got that from a finn) People say danish sounds most like norwegian but in reality danish is related to swedish where norwegian is from the other branch of scandinavian languages, I think the difference is the accent, if you ever hear a dane speak english then there's a big difference in the fullness, or rather lack of, in the accent from a dane vs a swede, and norwegians they sound like they're singing, rhythm. Incidentally, icelandic is said to be very close to the orignal common language spoken during the viking-era.

Frank

In answer to your question about feel and movement of the controls, the simple answer is, each plane is different!  Yep, even among the same model!  Now, the travel of a given control is regulated by specs, but a lot goes into how well a plane is "rigged", meaning how well the cables that adjust the flight surfaces have been calibrated.  They can be within spec, but still feel slightly different even among one plane to the next.  Big variances in feel and control play can be felt when you're dealing with different models of aircraft too.  For instance, a 727's control yoke and pedals will feel much different than an Airbus 300's.  And aircraft with true "fly-by-wire" systems will feel different than those with mechanical linkages or actuators.  Typically, for a Cessna 172, the control yoke goes from the 270-90 degree position to the 000-180 degree position stops in both left-and right directions.  Forward and backward play on that yoke can be as much as 4-5 inches or so from "neutral" to full back in the stomach for a full stall, and same in the forward position from neutral.  The rudder pedals, if adjusted properly, can feel more like a brake pedal on a riding lawn mower.  Also, on some aircraft, the rudder pedals have "toe brakes", where the top half of the rudder pedal can be pitched forward by your foot to actuate the brakes while still being able to move the pedals left and right to steer the rudder, and possibly the nose gear if it's stearable.

I wish I could describe it better, but it's really difficult to relate due to the variances.  I've flow C-172's, C-152's, PA-128's, C-23's, and various others, including a Ford Tri-Motor, and each one has a very distinct feel.  Some of them have very "heavy handed" controls, others are light as a feather to move.  And if you get into military planes, the fly-by-wire systems are more like using just one hand to move a joystick around a little and maybe using your rudder now and then tactically.
We're going to have to come in pretty low!  It's just one of those things you have to do... when you land!  -- Ted Striker - Airplane!

Offline Ted_Stryker

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Re: Flight Sim
« Reply #32 on: March 28, 2006, 11:23:32 PM »
Btw I was wondering, how much can you move a real plane's controls? (sorry fi I asked this before I can't quite remember).
One particular interest is also the pedals, how heavy are they? Are they like pushing down on the clutch of a sportscar or more like the throttle-pedal? And if it's light then could it work to design hanging pedals a bit like the throttle on a car for a more relaxing seating-position (wheel-brakes would be placed seperately, possibly as seperate pedals between the rudder-pedals).

And speaking of brakes, how does a plane handle on the ground? In MSFS it's like skidding on soap, one wrong flex of the rudder and the plane goes into what I think is called a Ground Loop (spin around like a car with locked rear-wheels at forward momentum).

And speaking of brakes, how fast can a small GA plane stop anyway? I assume that the lift of the wings are a factor even under stall-speed but can that be helped by pushing forward a bit on the yoke, or retracting flaps to reduce lift and thus put more weight on the main wheels to improve grip?

Edit: Flyingblind I'm actually danish, men jag kan pratta en del svenska og selvklart forstå det da dansk och svensk are beslektade språk i motsætning til norsk (that last part was attempted swedish, swedes and danes, and norwegians can mostly talk to each other on native languages since they're closely related, kind of a bond that I don't think many other countries in the world share). I normally call myself scandinavian instead of european since it fits more precisely culturally although even in Denmark I'm an excentric and don't really follow any normal class-type behavioural patterns, but that's mostly only in a good way. Btw, that you said sounded or at least looked more like finnish that I believe is related to the languages in your area isn't it? (I got that from a finn) People say danish sounds most like norwegian but in reality danish is related to swedish where norwegian is from the other branch of scandinavian languages, I think the difference is the accent, if you ever hear a dane speak english then there's a big difference in the fullness, or rather lack of, in the accent from a dane vs a swede, and norwegians they sound like they're singing, rhythm. Incidentally, icelandic is said to be very close to the orignal common language spoken during the viking-era.

Frank

In answer to your question about feel and movement of the controls, the simple answer is, each plane is different!  Yep, even among the same model!  Now, the travel of a given control is regulated by specs, but a lot goes into how well a plane is "rigged", meaning how well the cables that adjust the flight surfaces have been calibrated.  They can be within spec, but still feel slightly different even among one plane to the next.  Big variances in feel and control play can be felt when you're dealing with different models of aircraft too.  For instance, a 727's control yoke and pedals will feel much different than an Airbus 300's.  And aircraft with true "fly-by-wire" systems will feel different than those with mechanical linkages or actuators.  Typically, for a Cessna 172, the control yoke goes from the 270-90 degree position to the 000-180 degree position stops in both left-and right directions.  Forward and backward play on that yoke can be as much as 4-5 inches or so from "neutral" to full back in the stomach for a full stall, and same in the forward position from neutral.  The rudder pedals, if adjusted properly, can feel more like a brake pedal on a riding lawn mower.  Also, on some aircraft, the rudder pedals have "toe brakes", where the top half of the rudder pedal can be pitched forward by your foot to actuate the brakes while still being able to move the pedals left and right to steer the rudder, and possibly the nose gear if it's stearable.

I wish I could describe it better, but it's really difficult to relate due to the variances.  I've flow C-172's, C-152's, PA-128's, C-23's, and various others, including a Ford Tri-Motor, and each one has a very distinct feel.  Some of them have very "heavy handed" controls, others are light as a feather to move.  And if you get into military planes, the fly-by-wire systems are more like using just one hand to move a joystick around a little and maybe using your rudder now and then tactically.


In answer to braking and ground handling....

Again, a lot depends on the plane itself, how it's rigged and designed, and the weight of the plane.  In a light GA aircraft, say a C-172, if you combine aerobraking along with using the brake pedals, you can stop that plane in a very, very short distance.  The pilot's operating handbook has different figures for stopping distances under various conditions, so your best answer is to look up that data for the particular plane in that model's manual.  Aerobraking, by the way, is the technique of using as much drag as possible, by keeping the nose up until it won't fly anymore after the mains touch, and using full flaps.  Once you're slow enough, you can use the brakes effectively and stop the plane in short distances.   In fact, such techniques are drilled as part of one's training towards their private pilot certificate in the "Short Field Landing" training curriculum.  In a short field landing the technique is to use the slowest possible approach speed, touch down as close to the start of the usable runway area as possible, keep full flaps engaged, power at idle, and keep the nose up as high as possible without taking the plane up off the runway surface.  Keeping this held with the yoke coming back to you as airspeed bleeds off, if done right, will have the stall warning horn going off on the runway prior to the nose settling itself down as lift goes.  On most designs flaps add lift only at the first setting position, 10 degrees on a C-172, with subsequent lowering of flaps adding more drag than lift.  This is also why on a short-field takeoff, one uses partial flaps.  It gives you more lift with those first setting points and helps you get up into the air at slower speeds. 

You are correct about a ground loop.  Most commonly this happens in "tail dragger" aircraft, but it can happen with a conventional "tri-cycle gear" plane too.

Flight simulator taxi operations in MSFS are not easy to do.  It requires constant adjustment of power and rudder and braking.  In the real plane, one uses a bit more power to start moving the plane, then pulls power back to a lower setting.  One normally uses the brakes sparingly (or should) during taxi operations, and uses the throttle to keep from moving the plane at more than a fast walking pace.  Left-right corrections are a constant thing on the ground when moving a GA aircraft with a tri-cycle gear, but in a taildragger it is even moreso.  Part of the problem with taildraggers, that leads to ground looping, is that you can't see straight ahead because the nose is high, so you can only see out the sides.  One taxis a taildragger using a series of S turns to look out the sides to keep taxi centerline.  If you do this too fast, and/or at too high a speed, hello ground loop!  You don't even have to have the brakes on to ground loop a taildragger... just too much input for the tailwheel.  On a taildragger, the tailwheel, not the nose wheel, is moved by the pedals (if it's a steerable tailwheel and not dependent purely on rudder).  As you might imagine, it's tougher to taxi a taildragger than a tri-cycle gear airplane.


Hope this helps :)
« Last Edit: March 28, 2006, 11:31:21 PM by Ted_Stryker »
We're going to have to come in pretty low!  It's just one of those things you have to do... when you land!  -- Ted Striker - Airplane!

Offline Gulfstream Driver

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Re: Flight Sim
« Reply #33 on: March 28, 2006, 11:49:00 PM »
Control feel also depends on how well you trim, which reduces control pressure felt in the yoke.  Most airplanes don't have aileron trim, but most, if not all, airplanes have elevator trim.  If it's not trimmed properly, it can feel like your pushing on a brick wall. 

Also, there's a reason almost every GA aircraft has either toe brakes or heel brakes on the rudder pedals.  There are models with brakes separate from the rudder pedals, and they increase your workload quite a bit.  If you think about it, when your on the runway, you need both rudder and brake control available.  If you have to take your feet off the rudder pedals to operate the brakes, you lose rudder control.  Could be a bad deal.
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Offline Ted_Stryker

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Re: Flight Sim
« Reply #34 on: March 28, 2006, 11:56:18 PM »
Control feel also depends on how well you trim, which reduces control pressure felt in the yoke.  Most airplanes don't have aileron trim, but most, if not all, airplanes have elevator trim.  If it's not trimmed properly, it can feel like your pushing on a brick wall. 

Also, there's a reason almost every GA aircraft has either toe brakes or heel brakes on the rudder pedals.  There are models with brakes separate from the rudder pedals, and they increase your workload quite a bit.  If you think about it, when your on the runway, you need both rudder and brake control available.  If you have to take your feet off the rudder pedals to operate the brakes, you lose rudder control.  Could be a bad deal.

True... forgot to add that about the trim :)  Thanks :)
We're going to have to come in pretty low!  It's just one of those things you have to do... when you land!  -- Ted Striker - Airplane!

Offline Gulfstream Driver

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Re: Flight Sim
« Reply #35 on: March 29, 2006, 12:00:58 AM »
You bet.   ;)
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Offline Frank N. O.

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Re: Flight Sim
« Reply #36 on: March 29, 2006, 12:28:57 AM »
Wow, some really good replies, thank you all :)

I actually also thought that the forces might depend on the airspeed although I've seen some rudders and ailerons have a part that sticks forward of the axis that might act like an aerodynamic force-equalizer although that would also cancel the aerodynamic force wouldn't it?

The idea with the seperate wheel-pedals were to be designed so they physically pressed down the rudder pedal too (one of my concept-ideas uses seperate left/right drag rudders so like the Long-EZ the rudder pedals would not be connected but of course I don't know if it would work in the real-world (in case rudder-trim is needed for straight flight) even though the plane is to be designed with counter-rotating props on the centerline to make sure it didn't rotate the plane when changing power etc. and it's not a heavy load plane either so not too much weight difference).

I sadly never got to use the toe-brakes on the Cardinal since I didn't need them so I'm not sure how they felt, or how the ergonomics are, I hope I can try that someday though. Did you know that someone used that and designed a combined brake and throttle for a SAAB 9000 like that? The toe-pedal part was the throttle and then the normal brakes, meant to allow faster response-times for emergency stops. I don't think that works in the real-world though, the ergonomics surely wouldn't work for my ancle and knees (I've had my right ancle twisted almost 90 degrees as a teenager twice in two months giving me a stretched muscle-band(?) and my right knee dislocated when getting in the car a few years ago, snapped sideways 10cm inwards, but luckily snapped back into place but still another stretched set of muscles, so I'm not fond of strained ergonomics, but of course I still want control and safety above all).

I forgot to ask something about the brakes, I read that Dunlop invented the ABS system for the Concord and then it went on to other planes and cars, the first one also being the first AWD sportscar, the Jensen FF, but does GA planes have ABS and if so, can you feel that in the pedals, is there even a power-assistance on plane brakes like on a car of the same weight?

Hmm, maybe I should've asked this in a seperate thread not under sims but I hope it's ok, otherwise feel free to move to a seperate thread, I think at least some forum softwares can do this. Although some of the questions about the feedback was also to get an idea on what to do to get a reasonably realistic weight in the sim-controls I hope to make for. No idea where to find a real yoke in Denmark though, but on ebay UK there are tons of parts, even from prototypes allegedly, like from the TSR2 and early SR71 and Space Shuttle helmets, far out, maybe too far out to be real.

Frank
"When once you have tasted flight, you will forever walk the earth with your eyes turned skyward, for there you have been, and there you will always long to return."
— Leonardo da Vinci

Offline Ted_Stryker

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Re: Flight Sim
« Reply #37 on: March 29, 2006, 05:01:38 PM »
Wow, some really good replies, thank you all :)

I actually also thought that the forces might depend on the airspeed although I've seen some rudders and ailerons have a part that sticks forward of the axis that might act like an aerodynamic force-equalizer although that would also cancel the aerodynamic force wouldn't it?

The idea with the seperate wheel-pedals were to be designed so they physically pressed down the rudder pedal too (one of my concept-ideas uses seperate left/right drag rudders so like the Long-EZ the rudder pedals would not be connected but of course I don't know if it would work in the real-world (in case rudder-trim is needed for straight flight) even though the plane is to be designed with counter-rotating props on the centerline to make sure it didn't rotate the plane when changing power etc. and it's not a heavy load plane either so not too much weight difference).

I sadly never got to use the toe-brakes on the Cardinal since I didn't need them so I'm not sure how they felt, or how the ergonomics are, I hope I can try that someday though. Did you know that someone used that and designed a combined brake and throttle for a SAAB 9000 like that? The toe-pedal part was the throttle and then the normal brakes, meant to allow faster response-times for emergency stops. I don't think that works in the real-world though, the ergonomics surely wouldn't work for my ancle and knees (I've had my right ancle twisted almost 90 degrees as a teenager twice in two months giving me a stretched muscle-band(?) and my right knee dislocated when getting in the car a few years ago, snapped sideways 10cm inwards, but luckily snapped back into place but still another stretched set of muscles, so I'm not fond of strained ergonomics, but of course I still want control and safety above all).

I forgot to ask something about the brakes, I read that Dunlop invented the ABS system for the Concord and then it went on to other planes and cars, the first one also being the first AWD sportscar, the Jensen FF, but does GA planes have ABS and if so, can you feel that in the pedals, is there even a power-assistance on plane brakes like on a car of the same weight?

Hmm, maybe I should've asked this in a seperate thread not under sims but I hope it's ok, otherwise feel free to move to a seperate thread, I think at least some forum softwares can do this. Although some of the questions about the feedback was also to get an idea on what to do to get a reasonably realistic weight in the sim-controls I hope to make for. No idea where to find a real yoke in Denmark though, but on ebay UK there are tons of parts, even from prototypes allegedly, like from the TSR2 and early SR71 and Space Shuttle helmets, far out, maybe too far out to be real.

Frank

In answer to ABS brakes on GA aircraft....  while they may be on some upscale models that I haven't flown (and I can't say for sure here yes or no), I've never encountered ABS braking on any of the planes I've flown short of the high-end jets like the Saberliner, or similar.  And even there, it depended on the year of the plane, etc.  It would be a nice feature, but if one lands at the speeds indicated, unless you have some really adverse surface conditions, they shouldn't be needed.  If surface conditions are such that you need to jam on the brakes hard enough to activate the ABS system, my thinking is that one should probably have landed somewhere else :)   

Those extra little surfaces you may have seen along part of an elevator, or rudder, that look like their own little flap are trim tabs.  They are designed to apply forces to the airfoil surface to keep the airfoil positioned more easily at a given point.  They are manipulated in a GA aircraft by use of the trim wheel, and that in turn moves the surface.  The C-152, C-172, have these for the elevators, but not for the rudder.  Rudder trim on those is managed through a ground adjustable tab at the base of the rudder.  Usually a mechanic will bend that tab left or right as needed to accomplish the proper trim.  On other aircraft, a trim wheel for the rudder is also available that moves a tab like the one on the elevators, via a mechanical connection.

Sim controls for a PC are not like those with actual aircraft parts.  They may look similar, but they need a whole different set of inner workings to properly send digital information to the computer to let the pc know how the control is being moved.  In fact, most advanced simulators, such as those that the airlines use, cost more than the planes themselves because everything needs a digital translation.  Unless one is simulating a newer digital cockpit, you also need "A to D" conversion.. meaning Analog to Digital (and vice versa) so a standard looking airspeed gauge behaves like the real one.
We're going to have to come in pretty low!  It's just one of those things you have to do... when you land!  -- Ted Striker - Airplane!

Offline C310RCaptian

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Re: Flight Sim
« Reply #38 on: March 30, 2006, 04:20:18 PM »
ABS For Aircraft...


Large aircraft do have an ABS system only they are called "antiskid systems". It works by using a speed sensor on each wheel. If one wheel slows down more that the others( a skidding condition) it will send a pulsing pressure of hydraulic fluid to the brake on that wheel instead of steady pressure. This is called a modulating pressure. It is not felt through the rudder peddles and are usually found on aircraft that are very large with large landing gear. Usually used when there are 4 or more wheels on one main gear or an auto braking system. Auto brakes are when pilots preset the amount of braking they want to use on touchdown. Once the wheels are on the ground and meet the specified conditions it will automatically apply the brakes without the pilot pressing on the brakes.

 Just like in a car skidding wheels are less effective at braking and can lead to loss of control. I do not know of many GA aircraft that may have this system. It is a very heavy and spacious system. Plus small planes usually don’t skid unless the pilot lands with the brakes pressed or applies way too much pressure.

Offline Frank N. O.

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Re: Flight Sim
« Reply #39 on: March 30, 2006, 10:05:06 PM »
Thank you very much for the info, I guess ground-braking really isn't a problem with planes.

Regarding the short field operation, please correct me if I estimate wrong, but with the throttle all the way back to idle as described and full flaps wouldn't you have to dive quite steeply and thereby descend quite rapidly to keep the airspeed above the stall-limit? Requiring very precise timing for the flare not to hammer in the ground, like when performing auto-rotation on a helicopter.

Frank
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Offline Ted_Stryker

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Re: Flight Sim
« Reply #40 on: March 30, 2006, 10:46:47 PM »
Thank you very much for the info, I guess ground-braking really isn't a problem with planes.

Regarding the short field operation, please correct me if I estimate wrong, but with the throttle all the way back to idle as described and full flaps wouldn't you have to dive quite steeply and thereby descend quite rapidly to keep the airspeed above the stall-limit? Requiring very precise timing for the flare not to hammer in the ground, like when performing auto-rotation on a helicopter.

Frank

Actually, all you need do is follow the recommended approach speeds for that maneuver from the pilot's operating handbook.  Short field landings are not normally more steep than others, just happen at slower speeds (that's what the flaps are for... to allow you to fly slower without dropping out of the sky while also providing aerodynamic braking).  The steeper approach maneuver is the Landing/Takeoff over a 50 ft. Obstacle procedures, which have you at Vx (best Angle of climb/descent) so you can clear those nasty things they put in the way of the runway sometimes.  It can feel in those approaches that you are almost "falling towards the runway", but in a controlled fashion.

A "normal" landing with full flaps is what most pilots use.  And once you know you have the runway made (meaning you know if your engine cuts out that you'll still be able to glide to it), you can pull the engine to idle and even add the last notch of flaps if appropriate.  Flaps do two things for you on landing... A) Helps to slow the plane down by adding drag, and B) adding extra lift to allow slower flight.  The first 10% of flaps (on a Cessna 152 or 172) adds more lift than drag.  Anything beyond that first setting in that aircraft is adding more drag than lift.

One of the reasons why approach speeds are either close to, or at the best angle of glide is because if you do have an engine fail, you're already set up to glide it in without power.  On a Cessna 172 this is right around 70 KIAS (Knots of Indicated Airspeed).  Stall speed, meaning the speed at which the plane will fall out of the sky due to lack of sufficient lift being produced by the wings to counteract gravity, can be quite low.  In a C-152, for instance, with full flaps, it can be quite low indeed.  If memory serves (and please correct me if I'm wrong on this because it's been many years and I don't have a 152 P.O.H. in front of me), full flaps with power off stall speed can be down around 43 KCAS (Knots of Calibrated Airspeed).  With flaps up and power off, a C-152 will have about a 48 KCAS stall speed.  Both well below the recommended approach speed of around 70 KIAS.  In a C-172, stall speeds are: power off and full flaps - 47 KIAS, and power off no flaps - 51 KIAS.

Now, in a plane like a C-152 you have a ground rollout of around 475 feet on a "standard day" (standard pressure and temperature).  On a C-172, ground rollout for a normal landing is about 550 ft.

So, in summary, unless you have that 50 ft obstacle to clear, even on a short runway, you still fly the approach at the normal approach angle.  Coming in steep, or shallow, either way, can invite problems.  There are techniques like "slipping to land" where one purposefully uses cross-controls to swing tail one way, nose the other, and use the side of the aircraft as an aerobrake to lose a lot of altitude fast if you are high on an approach.  By the way, other than using a glide slope indicator on your VOR, you can also use the lights at a large number of runways called VASI or PAPI lights.  These are lights that show you if you are high, on glide slope, or low, by changing colors.  They are located adjacent to the runway you are landing on, and are an array of two sets of lights, one "above" the other (as percieved from the air) in the case of VASI (Visual Approach Slope Indicator lighting), or as a set of four or more lights in a row for a PAPI system (Precision Approach Indicator lighting).  The simplest to use is the VASI.  On approach you will see the lights change with your glide slope angle.  White over white means you are too high, Red over White means you are on glide slope, and Red over Red means you are too low.  An easy way to remember this is; "White over White descend in flight.  Red Over White everythings all right.  Red over Red.... I'm DEAD!".    If you want to practice this with a flight simulator game, try the approach for KSUS, KCPS, or KSTL (my local airports that have these systems), and give it a whirl.

We're going to have to come in pretty low!  It's just one of those things you have to do... when you land!  -- Ted Striker - Airplane!

Offline madpilot44

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Re: Flight Sim
« Reply #41 on: March 31, 2006, 12:33:08 AM »
Does anybody know if there are any choppers in x-plane? I've run MSFS for quite some time now, but I want to try x-plane, and would like to know if you can fly choppers in it, and how good the physics are compared to MSFS and real life. thanks
To most people, the sky is the limit. To those who love aviation, the sky is home.

Offline C310RCaptian

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Re: Flight Sim
« Reply #42 on: March 31, 2006, 04:06:47 AM »
All this talk about short field landings reminds me of some words of wisdom imparted to me by a bush pilot while I was in Oshkosh, WI:

1) Every landing is a controlled crash… the wing has to stall in order for it to stop flying. It’s the height above the ground that dictates when it’s a landing or an arrival.

 2) For a good pilot it’s not the getting in and landing that posses the problem… it’s being able to get back out afterwards...( take off distances are generally where an airplane uses most the runway.. especially when heavy) 

Question  Ted_Stryker : What does White over Red mean?????  (Got asked this on my commercial check ride)   ;D ;D

Offline Gulfstream Driver

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Re: Flight Sim
« Reply #43 on: March 31, 2006, 05:01:12 AM »
I always tell my students that a hard landing on a short field isn't necessarily bad.  If you touch down hard, you translate forward momentum (i.e. energy) into heat energy through friction between the airplane and the ground and through the suspension system.  The idea is to land harder than normal, but not to bounce.  You also want to be able to use the plane again.  Then, use full aerodynamic braking and full brakes (without skidding).  You can get a 172 stopped in just a few hundred feet.

A soft-field landing on the other hand, is exactly the opposite.  Add just a touch (less than 200 RPM) of power during your flare, and you'll settle right onto the runway without hitting or bouncing.

With both landing techniques it's important to fly all of your pattern speeds.  In the 172 I like 90 downwind to base, 80 on base, and 70 on final. 

With a normal landing, let the plane roll out on its own.  The charts in the book are figured this way, and it saves your brakes.   ;)  Just don't roll off the end.
Behind every great man, there is a woman rolling her eyes.  --Bruce Almighty

Offline Frank N. O.

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Re: Flight Sim
« Reply #44 on: March 31, 2006, 12:28:58 PM »
I tried a idle-throttle full-flap descent in MSFS2004 in the RealAir Skyhawk (made for and tested by a flightschool for use in training but given free for simmers as well) and I couldn't get less than 900 fpm down but the nose was so high up that it was right on the 50 kts ias stall-limit, maybe I could get a slower rate if I nose down and got some speed, in fact I'm positive that's how it works but I was just testing and due to lack of atmosphere and practical means I haven't used FS2004 for much other than fun flying and buzzing around in a Vigilante and Valkyrie.

About the yoke then I fully understand the controls are different, I was merely referring to the yoke itself, not the rods it's connected to, like the steeringwheel of a car. I already planned a simple system that should be able to seperate the two directional forces and keep a stable feel in the movement for the sim-control so the digital read-out would be precise and easy to construct. I can show the tiny Lego-mock-up I made of it here if you want, but I seem to be unable to upload any more files according to the forum.

Btw, did someone say they'd flown a Ford Tri-Motor in here? Wow! How, when, where?

Frank
"When once you have tasted flight, you will forever walk the earth with your eyes turned skyward, for there you have been, and there you will always long to return."
— Leonardo da Vinci