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June 9th 13, 06:53 PM
Of tow hooks and brakes

The Region 9 contest is done and of course today is the most wind free day since the contest started. To say the contest weather was breezy is putting it mildly.

The wind put a severe strain on gliders and pilot skill. The pilot skill was there but I think in several cases the pilots had the deck stacked against them right from the start by their gliders.

Why anyone is still using only a center of gravity tow hook is beyond my understanding. The same goes for original weak Tost wheel brakes.

Alternatives are available for almost every model glider now. Even the original Tost brake now has a hydraulic actuator available. I believe there are forward tow hook installations, factory approved, for every model glider that was here.

Expensive? What was the cost of attending the contest? What is the cost of repairing your glider not to mention the loss of use while it is being repaired? What about the emotional cost as you veer off the runway and hope the resulting ground loop does not break your tail boom?

We all talk a lot about safety, safety is not cheap. Soaring is not cheap, who said it was supposed to be? Lets put our money where our mouth is. Make you glider safer.

Will the insurance companies wake up one day and realize there are more launch accidents and claims with C.G. hook equipped gliders?

I may be hurting my bottom line as I do operate a glider repair shop at Moriarty, but I am sick of seeing needless damage done to gliders.

Robert Mudd
Composite Aircraft Repair LLC

Bill D
June 9th 13, 08:28 PM
Yep, CG hooks are for winch launch - nose hooks for aero tow. Bad things happen the other way around. You'll probably want to do winch launches eventually so keep the CG hook, just add a nose hook.

Drum brakes can work like disks if you let Vintage Brake do their magic. http://www.vintagebrake.com/


On Sunday, June 9, 2013 11:53:28 AM UTC-6, wrote:
> Of tow hooks and brakes
>
>
>
> The Region 9 contest is done and of course today is the most wind free day since the contest started. To say the contest weather was breezy is putting it mildly.
>
>
>
> The wind put a severe strain on gliders and pilot skill. The pilot skill was there but I think in several cases the pilots had the deck stacked against them right from the start by their gliders.
>
>
>
> Why anyone is still using only a center of gravity tow hook is beyond my understanding. The same goes for original weak Tost wheel brakes.
>
>
>
> Alternatives are available for almost every model glider now. Even the original Tost brake now has a hydraulic actuator available. I believe there are forward tow hook installations, factory approved, for every model glider that was here.
>
>
>
> Expensive? What was the cost of attending the contest? What is the cost of repairing your glider not to mention the loss of use while it is being repaired? What about the emotional cost as you veer off the runway and hope the resulting ground loop does not break your tail boom?
>
>
>
> We all talk a lot about safety, safety is not cheap. Soaring is not cheap, who said it was supposed to be? Lets put our money where our mouth is. Make you glider safer.
>
>
>
> Will the insurance companies wake up one day and realize there are more launch accidents and claims with C.G. hook equipped gliders?
>
>
>
> I may be hurting my bottom line as I do operate a glider repair shop at Moriarty, but I am sick of seeing needless damage done to gliders.
>
>
>
> Robert Mudd
>
> Composite Aircraft Repair LLC

slbair
June 9th 13, 09:45 PM
What is the approximate cost of adding an aero tow hook to a sailplane that is designed for it but does not have one?

Tony[_5_]
June 9th 13, 10:13 PM
Pulling the release before things get out of hand is pretty cheap, like I did on day 2. Brakes are like Goldilocks if you want to stay out of the repair shop. Too weak and here comes the fence at the end of that field. Too strong and there's a hole in your nose after the wheels lock up.

Don Johnstone[_4_]
June 9th 13, 11:02 PM
At 21:13 09 June 2013, Tony wrote:
>Pulling the release before things get out of hand is pretty cheap, like I
>d=
>id on day 2. Brakes are like Goldilocks if you want to stay out of the
>repa=
>ir shop. Too weak and here comes the fence at the end of that field. Too
>st=
>rong and there's a hole in your nose after the wheels lock up.

Yep simple rule of thumb. If your glider has a nosewheel then fit a brake
as strong as you like. If you do not have a nosewheel, as in most single
seaters fitting a strong brake is really a waste of time and money because
you cannot use it. Even the "weak" brakes fitted to gliders such as the
discus can only be used with care.
>

BobW
June 9th 13, 11:44 PM
On 6/9/2013 4:02 PM, Don Johnstone wrote:
> At 21:13 09 June 2013, Tony wrote:
>> Pulling the release before things get out of hand is pretty cheap, like I
>> did on day 2. Brakes are like Goldilocks if you want to stay out of the
>> repair shop. Too weak and here comes the fence at the end of that field. Too
>> strong and there's a hole in your nose after the wheels lock up.
>
> Yep simple rule of thumb. If your glider has a nosewheel then fit a brake
> as strong as you like. If you do not have a nosewheel, as in most single
> seaters fitting a strong brake is really a waste of time and money because
> you cannot use it. Even the "weak" brakes fitted to gliders such as the
> discus can only be used with care.
>
Having once owned a tail-dragging glider with "world's best brake" I can vouch
that having an "overly powerful" *and* easily modulatable brake is a wonderful
combination. (It was a hydraulically-actuated drum brake on a homebuilt HP-14.)

It was powerful enough to put the plane on its nose, while simultaneously
sufficiently modulatable as to (easily) permit braking heavy enough to lift
the tail without pitching onto the nose. Combined with world's most powerful
landing flaps, the plane was a joy to land, despite its Vee tail-feathers and
veering into crosswind tendencies (in which case I generally angled into the
wind as much as practicable, touched down with minimal safe energy and fell
more in love with large deflection flaps and the superb wheel brake)...

Bob W.

June 9th 13, 11:59 PM
On Sunday, June 9, 2013 4:02:31 PM UTC-6, Don Johnstone wrote:
> If you do not have a nosewheel, as in most single seaters fitting a strong brake is really a waste of time and money because you cannot use it. Even the "weak" brakes fitted to gliders such as the discus can only be used with care. >

You can not use the breaking power you do not have, but you can modulate the extra breaking power you do have. Better a scraped nose than a busted glider. And having a nose hook also lowers the odds of having to release and use all the braking power.

Having flown tail wheel gliders with too little and with too much power I prefer the one with too much braking power.

Robert Mudd

SoaringXCellence
June 10th 13, 01:14 AM
Another element I have observed is that many pilot wait until the end of the run to try the brakes.

At that point the elevator has no authority to keep the tail down. Better to hold aft stick with braking while you still have control of the pitch, earlier in the ground roll. This allows you to keep the tail down.

I know that with the ships I fly that are "tail draggers" the sooner you get rid of energy the easier the end of the ground roll.

It's a different approach than most pilots seem to use but it works well.

Eric Greenwell[_4_]
June 10th 13, 03:21 AM
SoaringXCellence wrote, On 6/9/2013 5:14 PM:
> Another element I have observed is that many pilot wait until the end
> of the run to try the brakes.
>
> At that point the elevator has no authority to keep the tail down.
> Better to hold aft stick with braking while you still have control of
> the pitch, earlier in the ground roll. This allows you to keep the
> tail down.
>
> I know that with the ships I fly that are "tail draggers" the sooner
> you get rid of energy the easier the end of the ground roll.
>
> It's a different approach than most pilots seem to use but it works
> well.

On my ASW 20 C, I would put the flaps in negative after touching down
and hold the stick back, allowing full braking power with no chance of
going up on the nose. Wait to end, the elevator wasn't very effective at
holding the tail down, reducing the braking force I could apply without
the nose going down - like Xcellence said.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)
- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm
http://tinyurl.com/yb3xywl

Ralph Jones[_3_]
June 11th 13, 03:16 AM
On Sun, 09 Jun 2013 16:44:23 -0600, BobW >
wrote:

[snip]
>Having once owned a tail-dragging glider with "world's best brake" I can vouch
>that having an "overly powerful" *and* easily modulatable brake is a wonderful
>combination. (It was a hydraulically-actuated drum brake on a homebuilt HP-14.)
>
+1 on "easily modulatable". My first glass bird had a drum actuated by
a motorcycle squeeze grip on the stick, and its cable was pitifully
stretchy...by the time I got to a very moderate brake application, the
handle would hit the stick and stop. I finally found it was identical
to the one sold for the CLUTCH linkage on a 125cc Bultaco motorcycle.

I finally found a cable assembly that had larger gauge cable and a
stronger housing, and it worked pretty well.

Besides, if the barbed wire is coming up, putting the ship up on the
nose will be OK with me, thank you very much.

Uncle Fuzzy[_2_]
June 11th 13, 05:17 AM
> You can not use the breaking power you do not have, but you can modulate the extra breaking power you do have.
That's sure the Truth! I love the G103 hydraulic disc brake! Unfortunately, I fly a Speed Astir most of the time, which uses the same miserable Tost Kobold Wheel the LS3 and 4 use. Stretchy cables aside, I have never seen a Tost Kobold wheel that DIDN'T have cracks in the steel (iron?) brake drum portion of the wheel. The Tost BIMBO wheel is nothing more than a scaled up Kobold. Of course, I have one of those in the Janus.
Vintage Brake can make the drum brakes work well (a fiend's libelle brake is very powerful (after Vintage Brake treatment), even though it's the tiny Lilliput wheel.
The downside is the wait. He runs a 4 month backlog most of the time. I don't know what he can do if the drum has the cracks that are so common.

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