Reading Glider Manuals?

[Spark]

...
If any experienced pilots have a bombproof method for doing this, I'd love to hear it. I'm guessing, though, that it just takes a lot of time and practice.

Scott

Scott,

As with most everything else, there is no silver bullet. As many have said before, you need a mixed bag of tricks.

I use a variety of techniques to lose altitude.

The technique I use most involves altering one of the 4 legs of an UDBF (Upwind/Downwindd/Base/Final) approach.

For HR in NW winds, I make a left-hand approach and I alter the D leg. I start at the upwind end of the field and I make my downwind run on the W side of the treeline over Mong's field. If I am too high, I go a bit wide (westward). If I am most of the way there and I am still too high, I may turn west and then do a 180 (picture S turns on the downwind leg). I do whatever I need to in order to arrive at the correct altitude to initiate my base and final.

You can vary any leg of the DBF - it doesn't have to have right angles in it and each leg doesn't have to be straight. You can vary the Upwind leg and/or 'initiate' the DBF, and/or vary the D and initiate the BF, and/or vary the B and initiate the F. What to do depends on how much room At Woodstock, I vary my upwind leg and enter the DBF at a predetermined altitude. At Fisher, I vary the downwind leg. At Bills or Jacks, I don't worry about it too much

I'll add a couple of other, more controversial techniques:

Fly slower than min sink, just above stall (aka mush). In general, not a I don't recommend this to inexperienced pilots. In the past, I have occasionally chosen to slow some types of gliders down and mush them (to lose altitude without moving forward). Note that I would only do this in calm conditions. It works, but can be risky.

And then there is the slipping turn (as mentioned previously, an advanced manuever) I wouldn't do it in an all-mylar topless (already tried it once too many times , but it works really well for a Falcon or some of the intermediate-class non-curvetipped wings.

On occasion, if there is someone else in the pattern at my altitude, I may choose to spiral (360) down to a half-downwind, base, final to avoid a conflict.

I wouldn't go so far as to say any particular technique is dangerous or stupid in general. Some techniques will be more dangerous than others based on factors such as the glider, the weather conditions, the number of other pilots/aircraft in the pattern and the pilot's skill level.

[jimrooney]

I'm not saying either approach style is better. Figure eights and DBF are obviously both excellent landing strategies.

There is a difference however and mixing the two together is often seen as a good option. This puzzles me. Figure eights are better in high winds and DBF is better in light winds. Switching from a high wind approach to a low wind approach as a first option? I can understand if you run out of options, but it should be the last trick in the bag. It's often the first trick in the bag because it's the most familiar one. The problem is that you've missed many other better opportunities to correct the approach and are now stuck with doing figure eights... you've needlessly painted yourself into a corner and now you've got one out.

So what throws people off?

Inconsistent approaches. All that voodoo that people do for whatever reason. If you approach the ground the same way every time, things get a lot simpler. If I've seen anything that messes people up, this is it. Changing five different things at a time... how are you supposed to figure anything out that way?

Adjusting your speed to change your glideslope. People get away with it on single surface gliders and then get frustrated when they move onto higher performing gliders. They haven't developed the skills they really need to develop to land well... primarily recognising paralax.

Paralax.
Paris doesn't hit his airgate by chance. He knows where it is and how to get there. Airgates are trickier to see than ground targets, but paralax is how you figure it out. It isn't spidey senses, it isn't voodoo, it isn't a mythical skill that only hightime pilots are blessed with. Paralax is taught as the primary landing skill for GA students.

[breezyk1d]

Explain the parallax in context of the discussion please?








-----Original Message-----
From: Scott [mailto:sw@shadepine.com]
Sent: Wednesday, November 02, 2005 12:08 PM
To: hg_forum@chgpa.org
Subject: Reading Glider Manuals?


Okay, here's a beginner's perspective (experienced pilots, please chime
in with some self-analysis about what you do).

I understand sighting angles. I understand parallax. I understand the
DBF approach, as well as figure-8s. (Of course I still need to practice
all these things more!)

The aspect of flying landing approaches that is most difficult for
beginners---where the textbooks are vague---is knowing exactly how best
to lose altitude to start your DBF. In other words, to have a good DBF
in moderate-to-light winds (without needing to do S-turns, etc.), you
need to arrive (as Dennis Pagen calls it) at the initiation point at the
right altitude.

Like I said, I need to practice this more (so no need to call out my
ignorance---I'm aware of it)...I'm just pointing out that this is the
most difficult part for a beginner.

The bottom line is, no matter how well you understand landing approaches
as a beginner, at some point in the process you simply have to have a
good feel for your glider's sink rate in different conditions, and you
have to be able to judge angles and altitude effectively. This takes
time---a lot of time. Not something that someone with 20 hours gets down
perfectly.

If any experienced pilots have a bombproof method for doing this, I'd
love to hear it. I'm guessing, though, that it just takes a lot of time
and practice.

Scott

[Scott]

Parallax is a fancy word that just means finding that point ahead (along your glide path) where the ground (or objects) appear to neither rise nor fall. It's a rough way to see---at a given moment---where your glide path is headed. (See p.156, "Judging Glide Point," in the Hang Gliding Training Manual---Pagen doesn't actually call it parallax in his book.)

Scott

[breezyk1d]

Okay, that answers my question. You are referring to judging the rise
and fall relative to a reference point. Thanks! -Linda










-----Original Message-----
From: Scott [mailto:sw@shadepine.com]
Sent: Wednesday, November 02, 2005 3:36 PM
To: hg_forum@chgpa.org
Subject: Reading Glider Manuals?


Parallax is a fancy word that just means finding that point ahead (along
your glide path) where the ground (or objects) appear to neither rise
nor fall. It's a rough way to see---at a given moment---where your glide
path is headed. (See p.156, "Judging Glide Point," in the Hang Gliding
Training Manual---Pagen doesn't actually call it parallax in his book.)

Scott

[brianvh]

There is a difference however and mixing the two together is often seen as a good option. This puzzles me. Figure eights are better in high winds and DBF is better in light winds. Switching from a high wind approach to a low wind approach as a first option? I can understand if you run out of options, but it should be the last trick in the bag. It's often the first trick in the bag because it's the most familiar one. The problem is that you've missed many other better opportunities to correct the approach and are now stuck with doing figure eights... you've needlessly painted yourself into a corner and now you've got one out.

Okay, so long as we are getting into details, you seem to be referring to a number of options if you've started on your downwind and suddenly realize you're gonna reach your base too high. I only know of three:

1. Increase your speed - works wonders on single surface, may get you in deep doo-doo on double surface.
2. widen your approach - this seems like the best option so long as you don't overdo it over trees.
3. throw in an extra turn to extend the base leg.

The first one isn't so good on a medium-high performance wing, the third one you don't seem to like, so are there really other options? Please help me think outside the box here.

[jimrooney]

It's not "thinking outside the box", this is the standard stuff. My critisism is all the other voodoo people add to this stuff for this reason or that. My term is "creative approaches" also known as reinventing the wheel. The dbf approach has been around for a good hundred years.

#1, get good at picking your 45.
You've got your staging area untill you're perpendicular to your spot to get it. Once you've got this, you're in the ballpark and shouldn't ever need to throw in Sturns. You may land a little long or short depending on how you pick your 30 and 15, but you'll be in the field. This is the one that messes people up and that I see the most voodoo action to fix.

Other stuff... widen up, narrow in, shorten legs, lengthen legs, cut corners. Basically change your flight path (not speed) to get yourself back on glideslope. The earlier the better. Once you're on final, there is only so much you can do. Even on final, you can accept that you're going to land long. You can shoot for the corners if you're going to overshoot into the trees. If you're so high that you need Sturns, then you've seriously missed all of your angles.

It's not like any of this is news to anyone. That's my point. There's nothing new here. It's the new stuff that scares me.

[Spark]

It's not "thinking outside the box", this is the standard stuff. My critisism is all the other voodoo people add to this stuff for this reason or that. My term is "creative approaches" also known as reinventing the wheel. The dbf approach has been around for a good hundred years.

I agree. It is all standard stuff, even 'creative' approaches you have labeled 'voodoo'. I always attempt to use consistent approaches for a particular site, but when 'sh-t' happens, I want to be able to adjust accordingly. When you shorten or lengthen a leg, widen, or cut a corner, then it becomes unique, and the term 'DBF' becomes a whole lot less descriptive.

Every landing is unique and consistency is something we try to project onto it. Frankly, the English language isn't adequate to describe and discuss flying concepts effectively. One persons's voodoo is another's consistency.

"A foolish consistency is the hobgoblin of little minds, adored by little statesmen and philosophers and divines"?


make my approachesUnfortunately, it can happen when the field is very active and you hit a massive thermal.

When you shorten or lengthen a leg, cut off or round a corner, when does a DBF

[jimrooney]

I guess we're talking to two different people about two different topics...

The stuff you're describing is more advanced "get your butt out of something" techniques, what I'm describing is "how do I hit my spot".

When I hear people planning on using figure eights in liew of other easier/safer corrections, or in this case full on 360s, that's when I decide to pipe up. I watch time after time as someone struggles with landing their first double surface glider because they've learned to adjust their airspeed and not their approach, or they just can't pick out that 45 all that well. Once they get past that crutch, *poof*, they're hitting their spot.

I do all kinds of funky stuff when I'm doing my own landings. But then, I'm choosing to do so... I've got lots of tricks in the bag.

You've got tons of hours. This stuff is second nature for you. Someone who's only flown a falcon is an entirely different story.