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eddiemac0
11-24-2004, 04:31 PM
After many failed attempts at landing heavier multi-engine craft, I slowly realized that I was coming down on my gear very hard as I bled my final ten to fifty feet of altitude (even at the slowest landing speeds), and crashing every time. More experimentation (and successful landings now http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif) has led me to believe that landing speed is not so important, but that the downward force of your touchdown is (at any and all speeds). Is this correct?

eddiemac0
11-24-2004, 04:31 PM
After many failed attempts at landing heavier multi-engine craft, I slowly realized that I was coming down on my gear very hard as I bled my final ten to fifty feet of altitude (even at the slowest landing speeds), and crashing every time. More experimentation (and successful landings now http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif) has led me to believe that landing speed is not so important, but that the downward force of your touchdown is (at any and all speeds). Is this correct?

vertical453
11-24-2004, 04:40 PM
no, because you should be flaring with no airspeed left on the verge of stalling. If you dont have enough airspeed and have to much altitude you will come down hard, make your approach low, this helps. Anyway, sure, you could land at 500mph but slowing it down and keeping it on the ground is going to be very hard.

ShadowHawk__
11-24-2004, 04:57 PM
Obviously if you were flaring with no airspeed you would fall out of the sky. If you're touching down too hard, increase your airspeed. Your plane should optimally land in a 3-point position (all wheels making contact with the ground at the same time, assuming a tail dragger). If you're hitting the ground too hard, your aircraft is producing less lift than it should, and it's falling faster. You can increase lift by either increasing angle of attack, or by increasing airspeed. Since a proper landing is at the angle of attack where all your gear touch down at the same time, then the only way is to increase the airspeed.

Hitting the ground at a high perpendicular speed is bad, hitting it at a high parallel speed doesn't do anything (within the context of the sim anyhow). Obviously in real life there are other complications to landing at high speeds, but in the game, it really doesn't matter much short of running out of runway.

Hope this helps.

Fennec_P
11-24-2004, 05:33 PM
The only time you really have to approach on-speed and do a 3-point, is when you are landing on a carrier.

Otherwise, it's a lot safer just to do a fast 2-point. All the runways in the game are really long. Braking hard is possible with back stick pressure to prevent flipping over.

Fliger747
11-24-2004, 06:38 PM
Modern heavy aircraft are flown at an approach speed of 1.3 VSO (power off stall speed). This will work OK in the game for large arcraft and will give good controllability. Approach with full flaps, coming over the threshold reduce power and flare slightly, flying onto the runway with a slightly nose high attitude as your speed bleeds off, lower the nose slowly to the runway.

Save a few of these as tracks and re-play them to anaylize where your problem is.

Real aircraft of the era had poor tires and brakes by modern standards, Hey, there's a war on buddy!

Mozzie_21
11-24-2004, 11:51 PM
On landing you should trim your plane to fly an attitude (pitch) that gives you your desired airspeed. If you want to slow down lift your nose a bit. If you want to speed up push your nose down a bit.

Similarly if you want to descend at a higher rate decrease your throttle. If you want to reduce your descent rate open your throttle a bit.


If you do this your plane will fly itself onto the runway. When you are almost on the ground, you should just pull your nose up slightly to flatten out and cut your throttle. Then let the plane settle onto the ground.

effte
11-25-2004, 06:55 AM
The important things about airspeed on approach:

* It must be high enough for you to avoid stalling in due to the wind gradient, gusts or required manoeuvres.

* It should be as low as possible to minimise the distance you float along the runway before settling onto it, thus reducing the landing distance required.

The approach speed, Vref, is typically set as a factor times the stall speed in landing configuratio. FAA sugests using 1.3 times Vs,0 if no Vref is specified. For small aircraft, 1.3 is also the figure suggested by the EASA.

Fly the approach at approach speed. As you approach the threshold, pull off power and gradually raise the nose. The aim is to have the aircraft skimming the runway with the wheels as close to the ground as possible. You will have to keep raising the nose as airspeed bleeds off. Eventually, your airspeed will be below Vs and the aircraft will stall onto the runway.

It was not easy in earlier versions of Il-2, as the tailwheel would be significantly lower than the mains before the aircraft stalled. It is still not easy due to the wing drop tendencies most aircraft have even in gentle stalls. Thus, a main-wheel landing as described by Fennec-P is often the best option.

Regards,
Fred

MrMoonlight
11-25-2004, 08:27 AM
Mozzie_21 is absolutely correct. What a lot of non-pilot simmers fail to realize (because it's somewhat counterintuitive) is that in most flight regimes, airspeed is controlled by pitch (AOA) and altitude controlled by power.

Airspeed is just one factor on approach. Sink rate (rate of altitude loss) is just as important. Keep an eye on your VSI. (if the VSI in your cockpit isn't in view on approach, adjust your cockpit view with the mouse to make sure it's clearly visible. That's what I do.)

As a rule of thumb, don't let your sink rate get faster than 500 fpm on short final. If your sink rate starts getting too fast, don't pull back on the stick - that will just bleed off airspeed and get you closer to stalling - instead, add in a skosh more power. A power increase at the given AOA will arrest the descent without making you faster airspeedwise.

As you flare, try to hold the aircraft a few feet off the runway with back pressure on the stick. To touch down, don't just abruptly cut the power. Instead, smoothly and deliberately reduce the power...the plane will settle on its own. Once the mains have touched, you can safely pull off the remaining power and begin braking, all the while maintaining back pressure on the stick.

High landing speeds are dangerous as they can lead to a lot of heavy bouncing and porpoising on touchdown. I don't think all of this is modeled in the sim but IRL, landing at too high a speed can have unpleasant consequences.

Just do like Mozzie and Flieger have explained above, and with a little practice, all your landings should be "greasers".

Happy Landings!

mortoma
11-25-2004, 08:52 AM
I've also found that a lot of newer people have a tendency to try and emulate the way the AI lands their aircraft. I have three words for this ( excuse the caps ), "DON'T DO IT"!!!! This is a big mistake because the AI come in way, way too shallow, this makes for a high throttle setting to maintain your approach, so it makes a much bigger difference when you chop your throttle. Unless you carry power all the way until touchdown, which is not the way you want to be landing most aircraft. In real life aviation, you only time you'd want to land that shallow is when you have to use less flap than normal due to high crosswinds, something that is not modeled in FB, at least not very well. The more steep the approach the better ( up to a point of course ).

A steeper approach is more favorable since if your engine quits, you can still glide in. Come in at a higher angle, about 15 knots ( 17mph or 27kph ) higher than stall speed with full flaps. Trim your plane on approach so you don't have to pull back far on the stick as you come in. Then about 50 feet above the ground at the end of the runway, chop your power completely. Slowly pull back on the stick and try to get parallel to the runway as you get close and then try and hold your wheel about a foot off of the runway as long as you can. Ideally you should land on all three wheels or close to it. A perfect 3 point landing in a tail dragger, unlike what they may tell you, is not necesary. But you want to get close to it at least. If my tailwheel touches within 3 seconds of my mains, I consider it a perfect landing. This should be your standard.

With a tricycle gear plane, you want you the main ( the two rearward ones ) wheels to touch first, although they don't to touch a long time before your nosewheel does. As long as they're on the ground first. If your maintaining a proper steepness to your approach in this sim you'll know it, because you'll only need about 30% throttle to maintain your proper approach speed ( VREF ).

MrMoonlight
11-25-2004, 09:28 AM
Good point, mortoma...don't copy the AI, that's for sure.

I agree with pretty much everything you say except for the part about chopping the power 50 ft above the runway. That'll work for light aircraft like a C172 or Piper Archer...they'll glide in quite nicely... but try that in a much heavier WWII fighter with a higher wing loading, and you'll be droppin' onto the runway like a rock. Heck, you don't normally even land a 3200 lb., 300 hp Beech Bonanza with the power at idle. You have to fly 'em all the way onto the runway with power. The sink rate of most all high performance aircraft increases dangerously fast if you chop the throttle on approach with full flaps. You have to hold the A/C a few feet off the runway with power and then gently reduce power til she settles...then you can power back to idle. That's the way I was taught and have been doing for years.

I haven't tried doing it in FB/PF, but that's the next thing I'll try later tonite. Something else for me to goof around with. Realistically, it shouldn't work...if it does, oh well..it's just a sim, I guess.

mortoma
11-25-2004, 09:42 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by MrMoonlight:
Good point, mortoma...don't copy the AI, that's for sure.

I agree with pretty much everything you say except for the part about chopping the power 50 ft above the runway. That'll work for light aircraft like a C172 or Piper Archer...they'll glide in quite nicely... but try that in a much heavier WWII fighter with a higher wing loading, and you'll be droppin' onto the runway like a rock. Heck, you don't normally even land a 3200 lb., 300 hp Beech Bonanza with the power at idle. You have to fly 'em all the way onto the runway with power. The sink rate of most all high performance aircraft increases dangerously fast if you chop the throttle on approach with full flaps. You have to hold the A/C a few feet off the runway with power and then gently reduce power til she settles...then you can power back to idle. That's the way I was taught and have been doing for years.

I haven't tried doing it in FB/PF, but that's the next thing I'll try later tonite. Something else for me to goof around with. Realistically, it shouldn't work...if it does, oh well..it's just a sim, I guess. <HR></BLOCKQUOTE>Yes, you're right. In most warbirds ( never flown one ) I'd think you'd want to wait until ground effect to chop. But in the sim I chop fairly high up in most planes, 20 to 100 ft. up, depending on the plane and it works just great. I never have to carry power all the way until touchdown in any of the planes. But yes, real life and the sim is different. Not by a lot but some. You're right about carrying power in most bigger planes but I don't know by experience because the heaviest plane I have ever landed is an old Beech Bonanza V-tail that a friend has. Apart from that, all my time has been in Cessna 172, 152, Piper Cherokee, Warrior, and a Cessna Cardinal. Sounds like normal approaches in the heavier planes you fly are a bit different. But what would you do if you lost power on final?? Seems to me you should know how to land any plane you fly with no power, just in case. Probably take a pretty steep approach to pull it off in the planes you fly but I'd want to know how to do it if I were you. Even a Antonov AN-225 Myira should be able to land with no power though. It would have to be steep though. And I for sure wouldn't want to be the one who had to do it!!

mortoma
11-25-2004, 10:07 AM
Another thing MrMoonlight, just by the type of planes you fly you are probably instrument rated and used to flying ILS approaches. An ILS approach is usually quite shallow and even in a 172, I'd carry some power in after that. But I fly VFR, as I quit my IFR training due to the 9/11/01 attacks and just never finished my training. A typical short final VFR visual approach is steeper, makes a difference. Although a lot of guys who fly IFR land shallow like that all the time since they get used to it. I sure don't. I come in steep when I use full flaps, even with a 172. I used to fly out of a grass strip field that had power lines at the north end so landings for runway 18 were excessively steep!! I'm used to it!! The steepness of landing us locals do at that airport using 18 would scare most average pilots not used to it......lol

Sakai9745
11-25-2004, 11:56 AM
I like Moonlight's comment on wing-loading. The Piper Arrow that I regularly fly has a relatively high wingloading due to it's hershey-bar wing, and to 'chop-n-drop' in that aircraft is ill-advised unless the pilot has a great feel for the aircraft for timing the flare. Most of the guys that I know that fly the Arrow, especially me, will carry a smidgen of power over the threshold, coordinating the flare with the final reduction of throttle for a sweet touchdown. The exception to the rule, of course, is a short-field landing.

In my instruction to new pilots, I describe a landing as 'getting the aircraft to stop flying a foot or two above the strip'. In PF, I've always favored using a 'soft-field' landing technique, which is used when landing on gravel or grass landing strips. It is identical to how Moonlight described except that power is never brought to full idle. In GA tricycle-gear circles, the resulting propwash over the tail surfaces keeps the nosegear from digging in; I find that 10% to 15% of power I maintain on the rollout creates keeps the tailwheel down for directional control as well as from nosing over when braking.

mortoma
11-25-2004, 01:29 PM
There's a lot of different techniques out there. I was instructed for my PPL by a Certified FAA examiner that had over 25,000 hours of time and flew both light observation fixed-wing and rotary wings in Viet Nam. He taught me nothing but chop and drop in the 3 planes I was instructed in, a Cherokee 180, Skyhawk II and a C152. If I would have tried to carry power someone would have been carrying me in a casket, cause he would have killed me, literally. The only time he allowed me to carry any power at all, was when he made me simulate a no landing light approach and landing at night. Which was wise of course, with no light to light up the runway. It was a scary experience even with power on.

Sakai9745
11-25-2004, 01:50 PM
No arguement that the 'chop-n-drop' technique is useful http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif. Uses less runway, and is critical for short-field landings. Just don't know about it for planes like those in PF.

MrMoonlight
11-25-2004, 02:35 PM
True, guys...nothing wrong with "chop and drop", provided it's done in the right aircraft. I learned to fly in a C172 and always landed without power. That's just the way it was done. And it's always better to be a little higher than too low. You don't want to be "dragging it in" with a high power setting on approach with those barn-door flaps hanging out at 30 to 40 degress. You can get behind the power curve real fast and that can end your flying career permanently. The old C172 I learned in had flaps that went to 40, but I never used that setting normally unless I was doing short field work with a high approach. The flaps on the more recent Cessnas only go to 30...reportedly because there were too many accidents with people coming in too low with full 40 and having to go-around and..well, you can picture the rest.

Mortoma...yes, I'm instrument rated, but I still fly my visual approaches relatively "normally". It's tough to gauge the "steepness" of an ILS approach when flying it anyway, since you're concentrating more on the HSI GS/LOC during the approach than looking out the window...that is, until you break out or start getting close to DH.

Sakai brings up a good point about the nosewheel "digging in"...even on a paved surface, once the mains are down, I never just relax the yoke/stick and let the nosewheel plop onto the runway. I'll try to keep the nose up for two reasons: It helps slow the aircraft faster (increased drag) and is easier on the gear. I usually hold the nose up until the speed bleeds off and gravity just naturally brings the nosegear down. I do this in FB/PF, too, with the P-38, P-39 and A-20. Seems to take a bit longer for the nosegear to come down in the sim, though... but the fields are pretty long in the game, so it's not much of a problem. http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

Heh, after all this discussion, I wonder if eddiemac0 has had any success now with his landings. I think we might have given him more info than he really wanted. LOL. But it's been cool discussing this with you guys. I think you'll agree that landing is the most challenging part of any flight (and the hardest thing to learn as a student pilot)...and it's never the same thing twice.

mortoma
11-25-2004, 03:35 PM
Yea, I haven't flown the Skyhawk I rented for a long time or any other plane for that matter. But I do remember I stopped using 40 degrees of flaps, especially with a lot of weight up front and none in the back. My instrument instructor was very heavy and I would get some really hard landings, even if I pulled the elevator all the way back to the stops!! Talk about nose heavy!! I also remember having to keep the wieght off of the nosewheel at ALL times, I mean all the way back on the yoke during taxi. Since to do otherwise in that particular bird you'd get really bad nose-wheel shimmy.

Tully__
11-26-2004, 12:04 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Mozzie_21:
On landing you should trim your plane to fly an attitude (pitch) that gives you your desired airspeed. If you want to slow down lift your nose a bit. If you want to speed up push your nose down a bit.

Similarly if you want to descend at a higher rate decrease your throttle. If you want to reduce your descent rate open your throttle a bit.


If you do this your plane will fly itself onto the runway. When you are almost on the ground, you should just pull your nose up slightly to flatten out and cut your throttle. Then let the plane settle onto the ground. <HR></BLOCKQUOTE>

This is the one, works with any plane in the game. Trim for a little over stall speed, use pitch for speed control & throttle for descent angle (glidepath) control. Pull out to level just as you're about to contact the runway and pull off the throttle and the plane will settle by itself when it slows through stall speed.

If you're a few km/h too fast it doesn't matter, it just means you'll take longer to settle.

You wont be too slow as you should have established a stable glide path early in the approach and you can't get a stable glide path if you're too slow.