If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#101
|
|||
|
|||
Future Club Training Gliders
On Sep 18, 8:23*pm, "
wrote: . Just to keep this discussion interesting, we can now argue whether a low energy tailwheel-first landing is OK or bad for a modern glider (assuming a reasonable sink rate at touchdown)... Kirk Ok....I'll start.........on a tail dragger glider.... landing *"ever so slightly" tail first touch down is a good thing..........if the approach is stable, and the sink rate is reasonable at touch down..........by touching the tail first, the main gear will come to the ground next, lowering the angle of attack on the wing, making it not likely for the glider to "bounce". Landing slightly tail first will also indicate that the glider is in the "low energy" state.....i.e. as slow as practical..(not as slow as possible, just as slow as practical) Landing slightly tail first should not put any undue stress on the airframe, tailwheel/skid etc, because the "weight" at the tail is very light..........the CG is far forward of the tail...........the glider will soon settle (softly) on the main gear, where the majority of the weight is taken by the robust structure / shock absorber etc there..... Note............this technique does not mean ....get close to the ground and jerk the stick back......this would cause the tail to slam into the ground with consideral impact......not good. Landing tail high in a taildragger glider is not a good thing........It indicates excess speed.......since the CG is behind the main gear, there is a tendancy of the tail to drop after main touch down, increasing the angle of attack, and possibly resulting in a *"bounce". Yes, a "wheel type" landing can be done successfully in a taildragger glider, but in requires a slight stick forward pressure after touch down to prevent bouncing, (by lowering the angle of attack.....) * and excessive speed, onger ground roll etc. Landing tail first in a nose dragger glider is not a good thing................. Landing tail first in a nose dragger will result in the main gear next touching down, but since the CG is in FRONT of this wheel, the tendancy is for the glider to continue to pitch forward (nose down) and contact the skid /nosewheel immediately..........as I mentioned earlier, the nose wheel or skid is not a "landing gear"...... IMHO......a nose dragger glider should be landed with "low energy" *(slow airspeed), but not so slow that the tail touches first (too slow)......The nose skid/ wheel should be held off the ground during the ground taxi, as long as elevator authority allows......when the nose finally drops, the ground speed is very slow........ Same technique works for 2-33, 1-26, *ASK-21, Grob 103...... This is far different from a "wheel type landing" and far different form "flying the glider on" Cookie Well said. I would differ a tiny bit in that a very slight tail low touchdown in a nose wheel glider isn't going to be a problem - but nothing more than a couple of inches low. |
#102
|
|||
|
|||
Future Club Training Gliders
On Sep 18, 5:53*pm, ray conlon wrote:
Having flown a number of different gliders and power planes over the years, no two of them handle or land the same, different aircraft take different methods of landing, what works for a Cessna 150 may not do so well in a Bonanza, or what works in a 2-33 wont wor'k *well in a Blanik,Lark,ASK21, etc. Thats why we have instructors to work us throught the transistion. Orvile and Willber were the only guys who had a valid reson to teach themselves to fly.. Having flown a number of gliders and power planes over the years, they are all pretty much landed the same - at the slowest possible speed allowed by the configuration of the landing gear (and the conditions at hand - for example a strong gusty crosswind may require a different technique than a calm day on a short field). It's that gear configuration that requires different techniques for different airplanes, not aerodynamics. That gear configuration is a driving factor in how 2-33s and Blaniks are landed vs how most modern gliders are landed (I say most because the PW-5 & 6 may be different, but I have no first hand experience in those two). If a student isn't taught the REASON for the specific landing technique (fixed attitude, slightly tail low, "flown-on" in 2-33s and Blaniks, due to weak tail vs tail and main at same time, min energy in glass such as K-21 or G-103) they will probably think that the first technique they are taught will apply to all future gliders. That can get very expensive. Kirk |
#103
|
|||
|
|||
Future Club Training Gliders
Tell me of any nose dragger where the method is to jam the stick forward right at touch down as the guy did in the 2-33 / Grob story above......... Cookie Under certain circumstances (off field landing in very short field) that is exactly the method that should be used - IF you are in a glider with a big skid and useless brakes. That's why it is there. But again - it's a specific technique for a specific condition, not to be applied universally - and especially not in the G-103! The skid is not the same as the nose wheel currently used, it serves a different purpose. Kirk |
#104
|
|||
|
|||
Future Club Training Gliders
On Sep 18, 6:52*pm, "
wrote: Please explain further........how is the correct landing procedure for a 2-33 going to result in a high energy landing in a Grob? IMHO....the correct landing procedure for a 2-33 (low energy, slow speed, nose high, tail low, etc) will result in a similar low energy landing in a Grob..........this would be a short runway landing, with little or no need for brakes...... Cookie So, when you are teaching landings to a student in a 2-33, do you first sit him in the front seat, level the wings, then hold the nose up until the tailwheel is on the ground and say "this is your landing attitude"? Do you do that in a G-103? Didn't think so. Where that tailwheel is relative to the ground is the difference. The landing angle of attack is probably about the same, but a student who learns to land on the main in a 2-33, nice and slow, but never touching the tailwheel, then who transfers that technique to the G-103, is a prime candidate for high energy landing problems. It's not a killer problem - but it needs to be taught correctly! Kirk |
#105
|
|||
|
|||
Future Club Training Gliders
On Sep 18, 7:23*pm, "
wrote: IMHO......a nose dragger glider should be landed with "low energy" *(slow airspeed), but not so slow that the tail touches first (too slow)......The nose skid/ wheel should be held off the ground during the ground taxi, as long as elevator authority allows......when the nose finally drops, the ground speed is very slow........ Same technique works for 2-33, 1-26, *ASK-21, Grob 103...... This is far different from a "wheel type landing" and far different form "flying the glider on" Cookie Agree on most, but disagree on K-21s and G-103s - their nose wheel is not the same as a nose skid, and they should be landed tail and main simultaneously, just like a taildragger. Reason? Look at the achievable angle of attack in the taildown attitude, between a 2-33 and a G-103. Tail low in a 2-33 is a significant angle of attack, nice and slow, but with the tailwheel still well off the ground. Tail low in a G-103, with the tailwheel not touching the gound, is going to be really fast! Kirk |
#106
|
|||
|
|||
Future Club Training Gliders
On Sep 19, 7:30*am, bildan wrote:
On Well said. I would differ a tiny bit in that a very slight tail low touchdown in a nose wheel glider isn't going to be a problem - but nothing more than a couple of inches low. What? Do you guys actually fly K-21s and G-103s? Is that what you teach your students? No wonder the Euros think we are a bunch of buffoons! Disgustedly, 66 |
#107
|
|||
|
|||
Future Club Training Gliders
At 16:07 19 September 2010, kirk.stant wrote:
On Sep 18, 6:52=A0pm, " wrote: Please explain further........how is the correct landing procedure for a 2-33 going to result in a high energy landing in a Grob? IMHO....the correct landing procedure for a 2-33 (low energy, slow speed, nose high, tail low, etc) will result in a similar low energy landing in a Grob..........this would be a short runway landing, with little or no need for brakes...... Cookie So, when you are teaching landings to a student in a 2-33, do you first sit him in the front seat, level the wings, then hold the nose up until the tailwheel is on the ground and say "this is your landing attitude"? Do you do that in a G-103? Didn't think so. Where that tailwheel is relative to the ground is the difference. The landing angle of attack is probably about the same, but a student who learns to land on the main in a 2-33, nice and slow, but never touching the tailwheel, then who transfers that technique to the G-103, is a prime candidate for high energy landing problems. It's not a killer problem - but it needs to be taught correctly! Kirk I did exactly that when teaching students to land a G103 except I would push down on the tail so that they could see the picture in front of them. The correct attitude is that where the main wheel and tailwheel touch the ground at the same time. The glider should then be kept running on the main and tailwheel for as long as possible, directional control is lost when the glider goes nosewheel down. |
#108
|
|||
|
|||
Future Club Training Gliders
On Sep 19, 10:16*am, "kirk.stant" wrote:
On Sep 19, 7:30*am, bildan wrote: On Well said. I would differ a tiny bit in that a very slight tail low touchdown in a nose wheel glider isn't going to be a problem - but nothing more than a couple of inches low. What? *Do you guys actually fly K-21s and G-103s? *Is that what you teach your students? *No wonder the Euros think we are a bunch of buffoons! Disgustedly, 66 You obviously misunderstood something I wrote. Yes, I have lots of time in those gliders and they do get landed slightly tail low - with the tail wheel an inch or two lower than the main wheel. It causes no problems and the landing is a little lower energy than a "two point" touchdown. In an off field landing, I'd probably have the tail a lot lower than that. |
#109
|
|||
|
|||
Future Club Training Gliders
On Sep 19, 10:05*am, bildan wrote:
On Sep 19, 10:16*am, "kirk.stant" wrote: On Sep 19, 7:30*am, bildan wrote: On Well said. I would differ a tiny bit in that a very slight tail low touchdown in a nose wheel glider isn't going to be a problem - but nothing more than a couple of inches low. What? *Do you guys actually fly K-21s and G-103s? *Is that what you teach your students? *No wonder the Euros think we are a bunch of buffoons! Disgustedly, 66 You obviously misunderstood something I wrote. *Yes, I have lots of time in those gliders and they do get landed slightly tail low - with the tail wheel an inch or two lower than the main wheel. *It causes no problems and the landing is a little lower energy than a "two point" touchdown. *In an off field landing, I'd probably have the tail a lot lower than that. I apologize for getting a bit testy, it was uncalled for. I think we are all arguing around the same basic concept; sometimes explaining those concepts can be challenging. Cheers, Kirk |
#110
|
|||
|
|||
Future Club Training Gliders
On Sep 19, 9:30*am, Don Johnstone wrote
: I did exactly that when teaching students to land a G103 except I would push down on the tail so that they could see the picture in front of them.. The correct attitude is that where the main wheel and tailwheel touch the ground at the same time. The glider should then be kept running on the main and tailwheel for as long as possible, directional control is lost when the glider goes nosewheel down. What is interesting is when you compare 4 different gliders: With a 2-33 (nosedragger), you have to pull the nose up until the tail touches, then lower it until it's at the correct landing attitude (you establish the range of available touchdown angle of attack). With a Blanik (taildragger), you have to raise the tail a little bit to show the desired touchdown angle. With a K-21 (nosedragger), you pull the nose up until the tail is on the ground, and finally, with a DG-1000 (taildragger), you just level the wings. Again, it's the gear configuration that is important, and why it's important is something the student needs to understand. Cheers Kirk |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Club Class Gliders | Sam Giltner[_1_] | Soaring | 4 | December 3rd 08 03:28 AM |
Basic Training Gliders | Derek Copeland | Soaring | 35 | December 26th 05 02:19 PM |
Basic Training Gliders | Justin Craig | Soaring | 0 | December 6th 05 10:07 PM |
Basic Training Gliders | Justin Craig | Soaring | 0 | December 6th 05 10:07 PM |
Soaring club close to NYC, with high-performance gliders | City Dweller | Soaring | 9 | September 29th 05 11:55 AM |