LAK-12 Question

Bill Daniels wrote:

If the one-man rigging system used "gate hinge" type root dolleys on the
trailer, then the wings could be swung out ~45 degrees to the
trailer/fuselage before the Udo-type wing dolly was attached to the wing CG.
Then, the wheels of the wing dolly needn't roll more than 4-6 feet when
rigging/derigging. One could pack a sheet of plywood to lay on soft ground
for the wing dolly wheels to roll on. That way, even if you landed in a
soft plowed field, rigging aids would still work.

If it's a soft plowed field, would you be able to get a heavy 40 foot
long trailer to the glider? And get it out when it's even heavier with
the glider in it? It wouldn't work around here in eastern Washington
state as the vehicles would get stuck, and many farmers would not like
the car and trailer on their plowed field.

I've never helped carry a Lak 12 out of a field, though it might be fun
to be the guy taking the pictures of the retrieve! Maybe Doug should
call all the people selling the Lak 12 and ask them why they are selling it.

--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly
* "Transponders in Sailplanes" http://tinyurl.com/y739x4
* "A Guide to Self-launching Sailplane Operation" at www.motorglider.org

"Eric Greenwell" wrote in message
newsk6%h.426$dj2.277@trndny02...
Bill Daniels wrote:

If the one-man rigging system used "gate hinge" type root dolleys on the
trailer, then the wings could be swung out ~45 degrees to the
trailer/fuselage before the Udo-type wing dolly was attached to the wing
CG. Then, the wheels of the wing dolly needn't roll more than 4-6 feet
when rigging/derigging. One could pack a sheet of plywood to lay on soft
ground for the wing dolly wheels to roll on. That way, even if you
landed in a soft plowed field, rigging aids would still work.

If it's a soft plowed field, would you be able to get a heavy 40 foot long
trailer to the glider? And get it out when it's even heavier with the
glider in it? It wouldn't work around here in eastern Washington state as
the vehicles would get stuck, and many farmers would not like the car and
trailer on their plowed field.

Is there any real difference between a 30 foot trailer and a 40 foot in this
situation? It's also worth pointing out that with the LAK's performance, it
shouldn't arise often.

Obviously, driving into a soft field is a bad idea that should be avoided if
possible but it's been done successfully. The LAK is heavier than, say, a
3-piece wing BG-12 or a Skylark 4, but I've helped get those out of plowed
fields. I recall some pilots carrying a 1000' spool of rope and a pulley
block to gently pull gliders to a gate where they could be derigged without
putting the trailer on the field.

The LAK WILL be more of a problem in retrieves but if you think about it you
can deal with it. The LAK is not as bad as my old Lark IS28b2 and I could
rig it solo..

Bill Daniels

Thanks for all of the feedback, guys. The weak lift performance is
certainly a plus here in Michigan. The downside issues are food for
thought. Paying for a hangar so it could be left rigged is out of the
question for me. Although I currently use an Udo dolly on my 15-meter
ship and that dolly is marvelous. It may make the LAK-12 assembly/
disassembly task acceptable.

Regards,

-Doug

Bill Daniels wrote:

If it's a soft plowed field, would you be able to get a heavy 40 foot long
trailer to the glider? And get it out when it's even heavier with the
glider in it? It wouldn't work around here in eastern Washington state as
the vehicles would get stuck, and many farmers would not like the car and
trailer on their plowed field.

Is there any real difference between a 30 foot trailer and a 40 foot in this
situation?

I would expect a much larger and heavier trailer to be a much bigger
problem. The tow car has got to pull a lot harder, with a greater risk
digging into the soft dirt, You can't manhandle it as easily if it gets
stuck.

It's also worth pointing out that with the LAK's performance, it
shouldn't arise often.

That depends on the pilot ^ - nobody needs to land in a field if it's
important not to, and at 20 meters, many airports and private strips are
unusable. The fear of a difficult retrieve or damage when landing on a
small airport makes the pilot fly more conservatively, which reduces his
soaring pleasure, and I suspect that factor is about half of the reason
these gliders are so cheap. The other half is the irritation of dealing
with them on the ground, or paying for a hangar.


The LAK WILL be more of a problem in retrieves but if you think about it you
can deal with it.

Agreed! A prospective owner should consider the hassles and if there are
acceptable solutions to them, and not be let the "bang for the buck"
figure crowd out consideration of these issues.

--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly
* "Transponders in Sailplanes" http://tinyurl.com/y739x4
* "A Guide to Self-launching Sailplane Operation" at www.motorglider.org

On May 5, 4:54 am, Doug Hoffman wrote:
I have noticed over the years that this glider sells for what seems to
be a very low price given that it is a near 50:1 glider. But I notice
lately that there are also some for sale on Wings & Wheels with
relatively low total time:

320 hours $21k
260 hours $20k
200 hours $15k

Other than the obvious issues of dealing with a more cumbersome glider
to assemble, ground-handle, and store, is there some other inherent
problem with these gliders? I would expect to see a lot more hours on
gliders of this vintage, and a higher price for gliders of this
performance.

TIA

-Doug

Tried to reply twice earlier but neither have showed up yet. Seems to
happen on the weekends.

For those interested in buying, join the Yahoo group LAK12 and review
some of the items there.

The LAK-12 flies fine. I haven't flown mine with water yet, but a
couple of owners report that ballast makes it a different, and even
better, glider. There are a couple of size considerations if you
have a long torso or big feet. Both can be accommodated to some
extent. It is pretty heavy, flapped, and I suspect some low-time in
glider owners haven't been comfortable in it and didn't get much
practice. The rigging effort required due to the poor trailer setup
probably limited the amount of hours they were able to get and
resulted in some intimidation regarding XC flying for others. The
LAK12 is a niche glider, comparable to the Nimbus 2, ASW-17, and
Kestrel 19, so attractive only to a smaller part of the market.

Rigging and the trailer are real issues, owing in part to the 230lb
wing panels and the poor trailer setup. Anyone considering buying one
should budget for some trailer modifications. Doing so will relieve
much of the problem. Domestic trailer replacement would cost about
$8000 plus rigging. I understand some of the trailers have structural
problems, and from what I've heard I suspect from excessive snow
loads. The rigging issues are largely part of the trailer design and
the wing root dollies. I've modified my door and rails with scissors
jacks and have replaced the aft trailer supports with longer sections
to reduce the fore and aft slope of the trailer dramatically and to
keep the fuselage dolly on the tracks to avoid the tail lift to get
the wheel down. Apart from that, the trailer tows well behind my F150
and the surge brakes work fine. The suspension is trailing torsion
arm with shock. The sprung section is steel, not rubber. It smooths
out the bumps. I think one owner had a suspension member fail.

I use an Udo dolly, which is not quite right for this glider. The
next stage will involve modifying the axle and inner wheel wells then
adding another stabilizing track and modified root dollies and a new
wing dolly. After that, I expect the glider with become one person
rig with no heavy lifting. I can rig now with one other person,
mostly for stabilizing the wings while moving them in and out of the
trailer. The scissors jacks help with the spigot and spar pin
alignments which are critical for assembly and finally with raising
and lower the gear. Taking a couple of extra minutes with alignment
before pulling the wings together makes it pretty easy. The real hard
part is lifting the wings in and out of the trailer saddles atop the
wheel wells and at the tip. It's the trailer design that's kept
people from flying them much XC or frequently enough to be really
comfortable with it.

I suspect several of the owners may have been low time glider drivers
and possibly first time private owners. This is my seventh glider and
I had rigged one a few times before and knew what the pitfalls were.
I've already solved some of the rigging issues and hope to finish the
rest before long. I've rigged and derigged a lot of glider types over
the years. The handbook for the LAK-12 says it can be rigged by 3-4
in 10 minutes. True, if it's the same crew each time, but where will
you find that these days? But that also means a lot of lifting. So
far I haven't heard about too many where the owners have taken time to
fix the short comings of the trailer and rigging issues. It's
doable. Have a peek in the lak12 yahoo group.

Plus side
Good forward and all around visibility.
Excellent performance. Thermals dry down around 41-42kts.
Tall undercarriage. Same oleo strut as Blaniks. Positive lock in up
and down position. Medium effort to raise and lower. Good wheel
brake with stick handle.
Two 12AH battery boxes for all those gadgets.
Good access to all controls and fittings.
Ballast system appears both well designed and functions fine from what
I'm told.
Ventilation.

So-so side
In board sections are flaps only. Out board sections are flaperons.
Tail emits a tone when thermaling on several, like blowing over the
top of a beer bottle.
Canopy is not strut supported, but held in open position by over-
center lock.
Original canopies are screwed, not glued, to frame.

Down side
Trailer design
Wing root dollies

Frank Whiteley

I fly a LAK-12 and love it. It is however kept rigged in a hanger.
Rigging is a pain if the guy in charge is clueless - but with time and
preparation - it can be made a lot less painless. Use wing stands
until ready for the final line-up and push and save the wingmans back.

It is easy and nice to fly empty - and very fast when loaded. Have a
few +500km flights in mine including a flight of almost 8 hours. There
is something very satisfying about 170km final glides.

It is also very strong and solid. Things are well put together. Mine
had a slightly off-white epoxy finish which should never crack. It has
subsequently been painted with a polyurethane paint which should also
be hard wearing and it has a glossy white colour. The control hook-ups
are a pleasure to use. And the canopy that locks into the open
position actually works very well. The fittings in the factory trailer
are also solid and the glider is very secure in the trailer. The
trailer is very long (12.5m) and weighs just over a ton loaded. I tow
it with a Landrover Freelander (2.0 TDI) and can tow comfortably at
the national speed limit (120km/h). The trailer has plenty of ground
clearance and towing out of rough fields is not a major issue.

I cannot get mine to spin - at the stall it just wallows around - or
the nose drops and the glider accelerates. It loops very easily. High-
speed flypasts are spectacular with the long wings.

All in all a great machine. I inherited an ASW-20 and had to decide
which aircraft to keep - as value wise they where the same. The LAK is
however 16 years newer and in far better condition. So it was goodbye
to the ASW-20.

Clinton
LAK 12 S/N 6229

50:1?
Land Out?

huh?????????

wrote:
50:1?
Land Out?

huh?????????

If you fly conservatively (well within the boundaries of your skill and
glider's performance), you will rarely, if ever, land out; conversely,
if you fly aggressively, you will land out often. The pilot determines
the risk of landing out, not the glider. The performance of the glider
will determine how far away from home the landout occurs. An aggressive
pilot with a Cherokee will land out conveniently close to home and be
retrieved in time for dinner, but an aggressive pilot in a Lak 12 might
not be retrieved until the next day, cold and hungry.

--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly
* "Transponders in Sailplanes" http://tinyurl.com/y739x4
* "A Guide to Self-launching Sailplane Operation" at www.motorglider.org

Eric referred to aggression level being a predictor of landout probability.

It is possibly semantics but to me aggression equates to pushing the limits
without consideration. An approach that generally results in running out of
height and ideas at some point. Even in a contest you have to finish tasks if
you want to score well, so there is a careful cognitive process of assessment of
conditions, personal and equipment performance and acceptable risk of landout to
determine how hard you push. When racing I generally have little to lose so I
can take risks - the top positions in the pack will be more averse to a landout,
because that will demote them. The winning by not losing idea of George Moffatt.

Same applies to personal flying. We should be balancing risk and goals
analytically.

My club is averse to XC flying, it is very hard to get anyone to retrieve you.
Since not getting retrieved is at best inconvenient and could be bad for your
health, I have to fly conservatively most of the time.

74 flights and 145 hours in my Std Cirrus - 1:37 on a GOOOD day. One land out,
at another airfield. With a nearly two hour average - including the winch
launches at sunset for a hangar landing, you can see I am generally flying in XC
weather. But the conservative flying style means I have only a couple of 300+ km
flights. We have pilots who own 1:29 performance ships that have never landed
out in 10 years of flying. Clearly glider performance is not a predictor of
landout probability.

Conversely, flying in regional contests I can (and do) take a lot more risk in
terms of land out. My flying has improved, as a result. I really believe that
glider pilots should be encouraged to explore the performance capabilities of
their aircraft. I disagree with the aggressive word though, to me this is all
about developing judgement. In this context aggression would be referring to
Instrumental aggression (aggression directed towards obtaining some goal,
considered to be a learned response to a situation - care of wikipedia.)
I would prefer to think of setting a risk level - What is possible today, and
what risk of landout can I accept? As a measure - I tend to be below the half
way position in contests. With my conservative flying meaning I fail to exploit
the conditions and capabilities fully. I generally share this area with the
other mis-judgers, either too conservative or trying too hard. (aggressive if
you like)

Now. I know Eric is a very experienced XC pilot so some opinions please.

Should we be landing out frequently enough to account for luck only, or more?
Should we ever intentionally fly aggressively as per the definition of aggression?

On May 7, 1:36 pm, wrote:
50:1?
Land Out?

huh?????????

You need to come check out some Arizona flyin'. There are times and
places when you are cruising in the mid teens, and you can't SEE
anyplace good to land down below!

And if you are down below 10k ft, you start sweating a landout...still
without seeing anyplace good to land...

Yeah, 50/1 sure is nice at times!

Kirk
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