![]() |
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 |
|
#1
|
|||
|
|||
![]()
Tim Taylor wrote:
'Maybe, but can you dive, lose the altitude, decelerate and get it on the ground for a tail wheel first, full stall landing?' Don't miss out an a VERY important lesson I nearly learnd the hard way, on the home field, in front of many of my friends. And that lesson is: 'NEVER let the disire to make a NICE landing over-rule the need to make a SAFE one.' If you are going into a short field, I would suggets that you NEVER hold it off to get a full stall, tail first landing. Get over the obstacles and get it on the ground. A wheel rolling through dirt will slow you down much faster than just about any set of divebrakes. And if working in concert with open divebrakes will stop you that much faster. My situatuion was a down wind landing after a training rope break. We had more than enough runway to land ahead, not quite enough behind to do a 180 and land back in the other direction, but not really enough to do a 360 and not end up as far down the runway. I didn't want to put it all the way at the upwind end of the field, so I told the instructor I was going to fly straight ahead to get lower, then turn around and land downwind. (Yes, you can see mistake number one, can't you!) We were as something between 300 and 400 feet in a 2-33. All went well on the upwind glide, good speed established, and a good turn to downwind. Trouble is, we didn't get as far upwind as I thought we would be, and we were going downwind faster than I thought. I (stupidly. See mistake number two!) was holding it off to get a smooth landing, with the end of the runway (and the cars and trees and all my fellow clubmembers) coming at us rather fast, when the insturctor said 'PUT IT ON THE GROUND!' Which I promptly did, put the nose skid on the ground, and started the turn to go off the side of the runway instead of into the cars and trees. We stopped before getting to any of the above (cars, trees, or the edge of the paved runway). Emphasis of the above lesson: Landing out, one mile from the airport, in the outflow of a thuderstorm, into the corner of center pivot irrigated field. So, the diagonal is maybe 700 feet, and there are power lines on the approch end. My last off airport landing was on a gusty day. The airplane went quiet and pretty much dropped in from about 50 feet. I grabbed the last of the flaps, rounded out, and touched down right at the edge of the field. For a photo from this landing, see: http://www.gliderforum.com/photos/sh...umid=122¤tpos= 3 So, I was a bit high, (it was a straight in to the field, with a 45 degree turn into the wind and to align with the diagonal of the field), and a bit hot, as I didn't want to end up in the lines. I rounded out, felt like the field was going by faster than I wanted, but knew I needed to stop. I eased the stick forward and put the nose and wheel into the dirt. The plane hopped up, and I put it back down. Not hard, but firm. Stopped, and still had at least 250 feet of field remaining. If the field is short, don't hold it off for a slow touchdown. Get it on the ground so it can get stopped before you get to trouble. Sorry, I got a bit away from the topic of the thread, but I feel it is important to remember that not every landing should be minimum energy at touchdown. There are times when you should stick it on, as you will then be minimum energy where it counts the most: at the edge of the safe landing and rollout area. OK, I should have changed this to 'The approach is important, but so is the landing!' Steve Leonard Wichita, KS |
#2
|
|||
|
|||
![]()
Steve Leonard wrote:
Tim Taylor wrote: 'Maybe, but can you dive, lose the altitude, decelerate and get it on the ground for a tail wheel first, full stall landing?' Don't miss out an a VERY important lesson I nearly learned the hard way, on the home field, in front of many of my friends. And that lesson is: 'NEVER let the desire to make a NICE landing over-rule the need to make a SAFE one.' Details snipped If the field is short, don't hold it off for a slow touchdown. Get it on the ground so it can get stopped before you get to trouble. Sorry, I got a bit away from the topic of the thread, but I feel it is important to remember that not every landing should be minimum energy at touchdown. There are times when you should stick it on, as you will then be minimum energy where it counts the most: at the edge of the safe landing and rollout area. OK, I should have changed this to 'The approach is important, but so is the landing!' Steve Leonard Wichita, KS What Steve said...it's ALL important. As a bare minimum, do what you need to do to get down, and stopped, safely. (I define 'safely' as being able to fly the same plane again without intervening repairs - to it OR to me!) I'm pretty sure the textbook (which we all own, right?) for the Flight Instruction 101 Course looks askance at newsgroup-originated instruction, but value can be found in many places. To me, value exists in threads as these...so long as your Critical Thought button remains functional. IMHO, so far Tim's numerical-exercise-based-question and the many responses it's generated, have contained lots of useful food for thought. Some has been more or less universally useful, some tending to the ship specific, and some controversial (natcherly each of us gets to define 'controversial'). It's in those non-universal 'gray areas' that real value can oftentimes be winnowed out...regardless of which view of the controversy one presently holds. My - U.S.-based - soaring experience tends toward the ship-specific (rather than, say, the ship-generalist). The bulk of my hours are in but 3 different types, while the rest of my time (in about 9 other types) totals probably less than 300 hours. Recognizing that all generalizations are false, including this one...it's my working conclusion, soaring 'ship-generalists' (often) tend toward the more dogmatic side of an inherently complex/nuanced situation, while 'ship-specialists' (often) recognize the presence of those nuances. I suspect the difference is ship-specific experience. Regardless, either approach will work...so long as the laws of physics aren't inadvertently toyed with. That noted, when it comes to trying to deepen my understanding of (and ability to effectively deal with) soaring problems, I tend to work from the general to the specific. Understanding the general helps me internalize underlying beliefs (and ultimately, actions), while dealing with the specifics requires respect for 'the devil's in the details.' Soaring by rote isn't something I'm comfortable with. Approaches - I fly mine with great faith in my own answer to the question, "What's more important in the pattern, airspeed or coordination?" (*That's* pretty general!) Approach Altitude/Angle - I've yet to encounter a sensible rationale to NOT make mine on the high side of whatever ship I'm flying's drag cone. N.B. What's high for one ship may be thoughtlessly low for another (e.g. unmodified early St'd Cirrus/Libelle vs. 'non-wimpy' AS W-20). Approach Airspeed - my target airspeed is consistent with field length/pattern-winds/personal currency...and I work damn hard to maintain my target airspeed to within a needle's width on the ASI. The yaw string gets equal respect and attention. Both consistent with 'everything else' that needs to be monitored during each approach... Real World patterns have included 'back side of the energy curve' final approaches, S-turn finals, high-speed/parasite drag finals, low approaches, high approaches...pretty much the gamut of what's been discussed so far. The only ones that have alarmed *me* (microbursts aside) were a few low finals (Majorly Stupid for any number of The Usual Suspect reasons), and one thought-I-might-be-too-high final (in a new-to-me ship). The rest were merely doing what needed to be done to get safely down and stopped. The fact others may have believed some of them occasionally abbie-normal has never been a major concern of mine so long as I'm not gratuitously putting others at risk by *being* abbie-normal. Touchdown Technique - mine is consistent with those same three approach factors. Consequently, I 'routinely' make 2-pointers and lowish-energy wheel landings, as well as occasional high-speed wheel landings (once at ~70 knots in a tail-dragging single-seat glider in a 25-30-knot direct crosswind). 'Style points' are nice, but 'safe touchdown/stop' trumps 'beauty.' My off-field experience seems similar to Tim's (i.e. mostly self-taught [not to be interpreted as exclusive of voluminous reading and considerable thought], perhaps 20 [all successful] instances, always with [at least] a full rectangular pattern). My eyeballs are more important than the altimeter in gauging height for OFL's, and I believe it's Highly Personally Risky to not be in a 4-sided pattern by the time a thermalling save is no longer an option. I guess my major point in philosophizing like this is to suggest that - except for the sensibility of not voluntarily tempting fate by inadvertently marginalizing the laws of physics - no one size fits all, once you're out there in the Real Soaring World, away from your instructors' govermentally-blessed hands. I learn (and sometimes re-learn) something every time I ride and soar with one, and am grateful for every instructor I've flown with, officially or unofficially. (Incidentally, that statement is true for all non-instructors I've flown with, too.) By way of conclusion, here's a thought problem for some dogmatic readers. I no longer worry about not having a slip in the landing arsenal of the ship I have most of my time in. Oh, it'll slip just fine, but its descent rate in a non-turning slip is significantly less than what it generates in the slip's absence. How can this be??? Regards, Bob - ruminatively - W. |
#3
|
|||
|
|||
![]()
Bob Whelan wrote:
By way of conclusion, here's a thought problem for some dogmatic readers. I no longer worry about not having a slip in the landing arsenal of the ship I have most of my time in. Oh, it'll slip just fine, but its descent rate in a non-turning slip is significantly less than what it generates in the slip's absence. How can this be??? Are you considering the descent rate in the slip *without* flaps all the way out? If not, then maybe the airspeed gets so low in a slip, because the Zoo-knee (or is it Zoo-nye?...only in Denver I guess ;-) ), that the vertical vector is smaller in the slip. Shawn |
#4
|
|||
|
|||
![]()
shawn wrote:
...its descent rate in a non-turning slip is significantly less than what it generates in the slip's absence. How can this be? Your airspeed is too high in the slip, probably because the ship does not have enough rudder to keep the nose high in the configuration you are using. The 2-33 and many other aircraft--both powered and unpowered--have the same problem. Jack |
#5
|
|||
|
|||
![]() "Bob Whelan" wrote in message ... By way of conclusion, here's a thought problem for some dogmatic readers. I no longer worry about not having a slip in the landing arsenal of the ship I have most of my time in. Oh, it'll slip just fine, but its descent rate in a non-turning slip is significantly less than what it generates in the slip's absence. How can this be??? Regards, Bob - ruminatively - W. Check the LS-4 Pilot Handbook. It says that slips with full airbrake are not so effective because airbrake causes a strong nose-down pitching moment, and airspeed increases excessively. In practice, I have found this to be so---Full airbrake alone produces a steeper approach than full airbrake plus slip. Is that the case in your ship? Hartley Falbaum "KF" USA |
Thread Tools | |
Display Modes | |
|
|
![]() |
||||
Thread | Thread Starter | Forum | Replies | Last Post |
Polar with spoilers extended? | Tim Taylor | Soaring | 85 | October 29th 07 09:16 AM |
New 304S Sailplane summary now available | Tim Mara | Soaring | 5 | January 6th 07 07:13 PM |
Discus polar curve at high speeds | [email protected] | Soaring | 12 | December 20th 05 01:59 AM |
Competition rules summary? | Ted Wagner | Soaring | 2 | January 21st 04 08:25 PM |
Turbo 182: correct mixture for final approach at high altitude? | Barry Klein | Piloting | 38 | January 15th 04 03:25 AM |