Avia Economia, Part 3

You Motorheads will like this Part :-)

Primary Gliders are designed to be dismantled. The fuselage breaks
down into two pieces. The horizontal stabilizer un-pins, as does the
rudder. Control cables are fitted with turn-buckles at key points,
allowing the cables to be divided, their free ends coiled and stored
in suitably marked bags, along with a dash of rat poison. The wings
of course, are designed to come off, the control cables are coiled &
bagged as mentioned above.

The break-down of a Primary Glider is mostly common sense but it also
reflects the components that make up its structure, and in doing so
defines the logical sequence of the manufacture of those components,
such as the rudder, stabilizer, aft fuselage and so on. This is worth
mentioning here because a Primary Glider is not a project with a
definable end. As soon as the first one is finished you will find
there is enough interest to begin collecting materials for another --
and enough people to keep it flying. But this post is about what to
do with your Primary when it's NOT flying.

You store it in its trailer.

In its dismantled state a Primary Glider occupies a space about 16
feet in length, 5 feet in height and four feet in width. Add an extra
foot to those dimensions for 'working room' and you have the
approximate dimensions of the glider's required storage space. Your
task is to turn those dimensions into a trailer.

Weight of the glider is not a factor here. At an absolute maximum a
Primary Glider will weigh no more than 180 pounds, assuming it is
built with ballast weights and a heavy skid. A more realistic figure
would be about 130 pounds. The weight you need to worry about is that
of the trailer's chassis & body. Here again, the weight is not very
much but its CG must be taken into account.

As a rule, start with the largest wheels you can find, with 15" or 16"
rims being preferred. Do a rough estimate of the trailer's weight and
locate the axle accordingly. When under-weigh a glider trailer can be
an awkward tow. It may be necessary to re-locate the axle or even to
add a ballasting mass. Be sure to take the required tongue-length
into account and provide the trailer with a steerable third-wheel and
jack-stands or stabilizers to keep the trailer firmly in place when
loading and unloading the glider.

The fun part of this assignment has to do with what you decide to
build the trailer from. Aluminum monocoque construction should be
high on your list since it provides an opportunity to introduce
Chapter members to riveting and the forming of aluminum parts. If you
live in a country where birch plywood is inexpensive, it will probably
prove more practical than aluminum. Fabric(!) over a wooden frame is
a valid method, assuming the trailer can be stored in a secure area.
Finally, if your funds are limited you may have to consider a steel
frame welded from conduit and covered with corrugated roofing panels.

I will include a couple of drawings of a typical glider trailer but a
big part of this project is to encourage input at the local level. We
can also expect to have the real glider folks point us toward some
photos of the real thing.

-R.S.Hoover

wrote in message
...
You Motorheads will like this Part :-)


I will include a couple of drawings of a typical glider trailer but a
big part of this project is to encourage input at the local level. We
can also expect to have the real glider folks point us toward some
photos of the real thing.


Ok, I don't qualify as a "real glider folk" - but I will do some pointing
anyhow:

http://www.soaridaho.com/Schreder/Co...1/Trailer.html

--
Geoff
The Sea Hawk at Wow Way d0t Com
remove spaces and make the obvious substitutions to reply by mail
When immigration is outlawed, only outlaws will immigrate.

wrote in message
...
You Motorheads will like this Part :-)


I will include a couple of drawings of a typical glider trailer but a
big part of this project is to encourage input at the local level. We
can also expect to have the real glider folks point us toward some
photos of the real thing.


Ok, I don't qualify as a "real glider folk" - but I will do some pointing
anyhow:

http://www.soaridaho.com/Schreder/Co...1/Trailer.html

--
Geoff
The Sea Hawk at Wow Way d0t Com
remove spaces and make the obvious substitutions to reply by mail
When immigration is outlawed, only outlaws will immigrate.

On Sep 19, 1:59*pm, "Capt. Geoffrey Thorpe" The Sea Hawk @See My
Sig.com wrote:


Ok, I don't qualify as a "real glider folk" - but I will do some pointing
anyhow:
-------------------------------------------------------------------------

Dear Captain,

Thank you for a very good first effort.

Some of the details we should expect from the Motorheads will be the
Tongue Height and Tongue Load, which will tell us which vehicles can
safely handle the load. In that regard, we are most interested in the
ability of the prime-mover to BRAKE the load rather than get it
underway.

We also need to put extra emphasis on the vehicle code for the State
in which the trailer is registered. Some rather silly rules are often
applied to trailers

-Bob

wrote in message
...

We can also expect to have the real glider folks point us toward some
photos of the real thing.

For better or worse, primarys are no longer a part of the "real" glider scene,
except in the occasional flight demo or as a museum exhibit. However, the very
first red-blooded USA-made Schweizer glider was a primary, the SGP 1-1. You can
see one here along with its original designers :
http://www.sacusa.com/corporate/history.asp .

In looking for this gem, I found it interesting that when one Goggles "primary
glider" the thing that floats nearly to the top is an old blog page from one RS
Hoover.

Even though I am a glider CFI, I have never had a chance to actually fly a
primary. In fact, the only guy I know who ever has flown one is dead. However,
this is the Internet, so lack of experience need not imply lack of opinion. ;-)

So here goes:

For several reasons, I don't think primary gliders should have any role in
initial flight training (a good subject for another thread) but I do think that
building a primary might be a worthy project for an EAA chapter. As Bob has
said, a building a primary could be a great and affordable learning experience.
Once built, it could be kept up in the hanger rafters to be taken down to be
flown by all at the annual chapter picnic.

When the members are done flying the thing and its time to break out the beer
and hotdogs, mount it on a little GC stand, point it into the wind, and let the
kids "fly" it to their heart's content. Any wind over 8-10 mph will likely be
enough to make the controls effective. With it fastened to terra-firma, the
kids won't be able to hurt it and it certainly won't hurt them.

If it ever happens, I would sure like to be there, and would hope to be allowed
to add a few seconds of PIC time to my logbook.


--
Vaughn

.................................................. .......
Nothing personal, but if you are posting through Google Groups I may not receive
your message. Google refuses to control the flood of spam messages originating
in their system, so on any given day I may or may not have Google blocked. Try
a real NNTP server & news reader program and you will never go back. All you
need is access to an NNTP server (AKA "news server") and a news reader program.
You probably already have a news reader program in your computer (Hint: Outlook
Express). Assuming that your Usenet needs are modest, use
http://news.aioe.org/ for free and/or http://www.teranews.com/ for a one-time
$3.95 setup fee.
.................................................. ........

Will poofread for food.

On Sep 20, 7:47*am, "Vaughn Simon"
wrote:


For several reasons, I don't think primary gliders should have any role in
initial flight training (a good subject for another thread)
---------------------------------------------------------------------------------------

Dear Vaughn,

Thank you for posting the URL of the strut-braced primary glider.
This is nearly an exact copy of the primary whose drawings I will
post... as soon as I find them :-)

But my view of who should be flying the thing is diametrically opposed
to yours. I want to get youngsters into the air as early -- and as
often -- as possible. By using ballast weights we should be able to
launch everyone, right down to nine year olds. With foot restraints,
shoulder harness and a hard-hat, there's virtually no combination of
attitude & altitude that could result in injury to the pilot. Indeed,
I would like to see a 'work-up' system, where the builders earn
'Flying Points' by working on the construction of the glider. In the
same way, once it its built, the 'Bungee Crew' earns 'Flying Points'
by stretching-out the bungees. Points may also be earned by returning
the glider to the launch point and doing maintenance. (I was allowed
to wash & wax wings. Didja know Primary Gliders have HUGE wings? :-)

Give a kid a task, you'd be surprised how well they do WITHOUT any
intervention from us know-it-all adults.

-R.S. Hoover

schreef:

Primary Gliders are designed to be dismantled.
(...)

Could someone kindly elighten me as to the definition
(more or less) of a PRIMARY glider?
Does it mean one's FIRST glider?
Or a glider for primary flight training?
TIA?

"jan olieslagers" wrote in message
...
schreef:

Primary Gliders are designed to be dismantled.
(...)

Could someone kindly elighten me as to the definition
(more or less) of a PRIMARY glider?

Try he http://en.wikipedia.org/wiki/Primary_glider

Does it mean one's FIRST glider?
No

Or a glider for primary flight training?
The name probably came from its use in training. My one (departed) friend who
had time in a primary did so as a member of the MIT gliding club in the 1940's.
They would tow the glider with an old truck. The student was (naturally) in the
glider, while the instructor sat in the back of the truck and yelled helpful
hints through a megaphone. He never mentioned bungee launching, but for more
advanced flights they converted the same truck to a winch by jacking up one rear
wheel and attaching an empty wheel that served as a pulley.

Vaughn

TIA?

On Sat, 20 Sep 2008 08:57:56 -0700 (PDT), "
wrote:

On Sep 20, 7:47*am, "Vaughn Simon"
wrote:


For several reasons, I don't think primary gliders should have any role in
initial flight training (a good subject for another thread)
---------------------------------------------------------------------------------------

Dear Vaughn,

Thank you for posting the URL of the strut-braced primary glider.
This is nearly an exact copy of the primary whose drawings I will
post... as soon as I find them :-)

But my view of who should be flying the thing is diametrically opposed
to yours. I want to get youngsters into the air as early -- and as
often -- as possible. By using ballast weights we should be able to
launch everyone, right down to nine year olds. With foot restraints,
shoulder harness and a hard-hat, there's virtually no combination of
attitude & altitude that could result in injury to the pilot. Indeed,
I would like to see a 'work-up' system, where the builders earn
'Flying Points' by working on the construction of the glider. In the
same way, once it its built, the 'Bungee Crew' earns 'Flying Points'
by stretching-out the bungees. Points may also be earned by returning
the glider to the launch point and doing maintenance. (I was allowed
to wash & wax wings. Didja know Primary Gliders have HUGE wings? :-)

Give a kid a task, you'd be surprised how well they do WITHOUT any
intervention from us know-it-all adults.

-R.S. Hoover

opinion without direct experience thankfully.
my read of primary gliders years ago was that they fell out of favour
because of spinal injuries on hard landings.
now these days we have polystyrene in blocks which is one of the most
useful el cheapo spinal protection systems on the planet.
you simply make the seat out of a big block of the stuff and hotwire
the seat profile to something comfortable.
you could hotwire each kid his/her own seat base and velcro it in
place. if the ballast to make each pilot weight constant was
incorporated at the very base of this block it would make a pretty
good spinal protection system.

these days as well we should be able to find an aerofoil with decent
characteristics and a docile stall break.

I'm not averse to Bob's line of thinking here. My original exposure to
the Primary Glider design was in an old book "The Model Aircraft Book"
by F.J.Camm the editor of 'Practical mechanics'
this details a number of designs from around 1935 and ends with a full
writeup and construction plans of a Zoegling type primary glider by
"E.W.T"

btw Bob I went out to the workshop and had a look for the book in the
middle of typing this. it sits here beside me. if you want I can scan
the 28 pages of the complete building article and email them over to
you.

btw the most perfect glider approach and landing I've ever watched was
completed by a little redheaded 17 year old girl in an air cadets
camp. she was flying the club puchatec solo, bought it in absolutely
wings level, rumbled the wheel on and came to a stop still wings level
then just slowly sat a wingtip down. when she hopped out and rose to
her full height she was only 4'8". what a little dynamo.

there is plenty of evidence that these ideas can work. those air cadet
camps used to solo between 10 and 30 kids every season.

Stealth Pilot

On Sep 20, 8:18*pm, Stealth Pilot
wrote:

my read of primary gliders years ago was that they fell out of favour
because of spinal injuries on hard landings.
Stealth Pilot
-------------------------------------------------------------------------------------

That should probably read 'head & spine.'

In the late 1930's they introduced an 'improved' primary having a
strut from the nose of the skid to the forward end of the 'towel-bar'
wing support. With only a SEAT BELT, these gliders soon became known
by an assortment of colorful -- but true names: Head Splitter, Face
Smasher, Jaw Breaker, etc.

Since the program had grown into a bureaucracy it was impossible to
immediately scrap the new, improved design and go back to the old
version.

Any of the 44xx series has a very good stall profile, especially if
you fatten the thing up: 4415 or even 4418. With a wing that fat the
stall is a sort of bobble rather than the nose-dives typical with the
sharp-nosed Gottengein series. Indeed, the thing's glide ratio is no
more than 8:1 if that. The use of a WHEEL instead of a skid alone
goes a long way toward preventing nose-overs. Ideally, the novices
are launched so their landing will be into an area of tall grass,
which acts as a brake. As they become more skilled you can move to
mown fields or even sand.

The need for a shoulder harness connected far enough aft so as to
prevent compression of the spine should be understood from the outset,
along with the need for foot/shoe restraints.

Ditto for a crash-hat.

But I think the best 'instructor' is the kids themselves, watching --
and critiquing -- every flight.

-------------------------------------------------------------------------------------

One of the best training devices is referred to as 'The Object' in a
derisive manner. It consists of the SCHEMATIC of a glider mounted on
a pivot. An engine fitted with a propeller blows on the thing and the
student is required to keep it balanced.

It sounds easy, especially if you're a pilot. Take it from me, it is
damned difficult. But most youngsters master it in only two or three
sessions -- often faster than an experienced pilot.

Nowadays, I wonder if we could afford the gasoline.

-------------------------------------------------------------------------------------------------

Whatever its short-comings, I contend that the primary glider is
worthy of consideration for the simple reason that we have run out of
other options.

I see people giving themselves a pat on the back for turning out one
or two pilots at a cost that would beggar the AVERAGE American, when
what we need are literally THOUSANDS of new airmen.

It's ironic that, given how much airmen have given to our nation --
from crop dusting to fighting fires and a thousand chores in between
-- history will show that the one group we've failed to help is
ourselves.

-R.S.Hoover