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November 15th 13, 11:29 PM
How do these two compare in terms of ease of handling. Ls4 is described as suitable for instruction as first solo. I have about 50 h but want an easy glider as the first machine. Price wise these two are not far apart so why not go with newer design? Also is the cockpit much smaller on Ls7 ( I am 190 cm and 100 kg).

Tom

LS3a Owner
November 16th 13, 04:10 AM
On Friday, November 15, 2013 4:29:53 PM UTC-7, wrote:
> How do these two compare in terms of ease of handling. Ls4 is described as suitable for instruction as first solo. I have about 50 h but want an easy glider as the first machine. Price wise these two are not far apart so why not go with newer design? Also is the cockpit much smaller on Ls7 ( I am 190 cm and 100 kg).
>
>
>
> Tom

I would start with which ship has the better seating for you, followed by the better trailer, gelcoat finish and instruments and canopy and ease of set up, and which one comes with the most usable extra's. Getting a good trailer and the whole set up is important. If the instruments are old you can easily spend 3-5 grand getting a good up to date tight panel. A lot to consider. Try and get a consultant to help you out if you are not sure of the fine points, and if your not sure what all the parts are really worth.

Chris Rollings[_2_]
November 16th 13, 07:16 AM
I was responsible for the flight testing for UK BGA Certification of both
types when they were first introduced into the UK.

The LS7 has a significantly better best glide in smooth and is a little
quicker in roll. However, the LS7 has a very sharp stall/spin departure
which I would not recommend to a low hours pilot, particularly one trained
in a regime that does not include spinning in its basic training. The LS7
gets some of its better glide angle from a higher aspect ratio, narrow
chord wing; when climbing in turbulent air the separation this causes
results in a substantially reduced rate of climb and straight glide
performance is reduced in choppy conditions. Fitting the vertical winglets
reduces both problems but doesn't entirely eliminate them.

The LS4 is considerably more benign, its only oddity is that if you climb
in thermals at the minimum safe and comfortable speed (normal practice in
most types) you get a noticeably worse rate of climb than if you fly 2 or 3
knots faster. That takes a little getting used to but once you have done
so it's a problem free aircraft.

I'm 6' 3" and weigh 190 lbs, I found both cockpits perfectly comfortable.

From what you say, I would recommend the LS4.

At 23:29 15 November 2013, wrote:
>How do these two compare in terms of ease of handling. Ls4 is described
as
>=
>suitable for instruction as first solo. I have about 50 h but want an
easy
>=
>glider as the first machine. Price wise these two are not far apart so
why
>=
>not go with newer design? Also is the cockpit much smaller on Ls7 ( I am
>19=
>0 cm and 100 kg).=20
>
>Tom
>

Chris Rollings[_2_]
November 16th 13, 08:31 AM
At 07:16 16 November 2013, Chris Rollings wrote:
>I was responsible for the flight testing for UK BGA Certification of bot
>types when they were first introduced into the UK.
>
>The LS7 has a significantly better best glide in smooth and is a littl
>quicker in roll. However, the LS7 has a very sharp stall/spin departur
>which I would not recommend to a low hours pilot, particularly one traine
>in a regime that does not include spinning in its basic training. The LS
>gets some of its better glide angle from a higher aspect ratio, narro
>chord wing; when climbing in turbulent air the separation this cause
>results in a substantially reduced rate of climb and straight glid
>performance is reduced in choppy conditions. Fitting the vertical
winglet
>reduces both problems but doesn't entirely eliminate them.
>
>The LS4 is considerably more benign, its only oddity is that if you clim
>in thermals at the minimum safe and comfortable speed (normal practice i
>most types) you get a noticeably worse rate of climb than if you fly 2 or

>knots faster. That takes a little getting used to but once you have don
>so it's a problem free aircraft.
>
>I'm 6' 3" and weigh 190 lbs, I found both cockpits perfectly comfortable.
>
>From what you say, I would recommend the LS4.
>
>At 23:29 15 November 2013, wrote:
>>How do these two compare in terms of ease of handling. Ls4 is describe
>as
>>=
>>suitable for instruction as first solo. I have about 50 h but want a
>easy
>>=
>>glider as the first machine. Price wise these two are not far apart s
>why
>>=
>>not go with newer design? Also is the cockpit much smaller on Ls7 ( I am
>>19=
>>0 cm and 100 kg).=20
>>
>>Tom
>>
>

Damned thing has clipped the last letter off every complte line.
>

noel.wade
November 16th 13, 10:07 AM
Not to take anything away from Chris' comments; but since he discussed the stall characteristics in terms of safety I'd also like to point out another safety issue to ponder: the LS-4 does _not_ have automatic control hookups.. So one thing to consider is your own attention to detail and how you feel about your ability to safely and thoroughly rig & check your ship (especially on a booming day and/or with distractions). If you _always_ use a checklist and/or do a good positive control-check it should be no problem; but if you find yourself in a hurry to fly or you are someone who is less detail-oriented then the auto-hookups of a later ship (like the LS-7) make rigging easier and safer.

Having said that, I have flown an LS-4 a few times and thought it was an absolutely delightful ship. I have never flown a '7 but one of my local buddies did. When flown properly it seemed to perform really well and didn't seem to pose my friend any difficulty (however he has enough experience under his belt that any adjustments he made were probably subtle and automatic).

Bottom-line: Its hard to go wrong with any of the fiberglass ships produced in the 1980's or later (LS-4 and newer, Discus and newer, DG-300 and newer, ASW-20 or '24 and newer). By that point in sailplane development a lot of the "quirks" of earlier designs had been ironed out and the gliders seem to be pretty consistent in having good handling and at least reasonable ergonomics (and that's been my experience, having flown many of these 1980's designs). So unless you're looking to absolutely maximize performance I say go with one of these ships that has great gelcoat and/or a great trailer - these two factors have a big impact on your enjoyment of the ship!

Just my 2-cents,

--Noel
(former Russia AC-4 and DG-300 owner)

P.S. Since I failed to mention it before: If your budget includes an LS-7 you might also look at an SZD-55. Not sure how their price compares in the market at the moment, but I found the SZD-55 to be really nice & easy to fly.. It'll be slightly more money, but for that $$ you get a newer glider (with automatic hookups and a few other modern amenities) that's somewhere in-between the LS-4 and the Discus in terms of flying-qualities & ergonomics.

JJ Sinclair[_2_]
November 16th 13, 01:19 PM
On Friday, November 15, 2013 3:29:53 PM UTC-8, wrote:
> How do these two compare in terms of ease of handling. Ls4 is described as suitable for instruction as first solo. I have about 50 h but want an easy glider as the first machine. Price wise these two are not far apart so why not go with newer design? Also is the cockpit much smaller on Ls7 ( I am 190 cm and 100 kg).
>
>
>
> Tom

I flew my 1000K in a LS-7, sweet machine after I fixed the spar bump in both lower wings. Good comfortable seat.
JJ

Dave Nadler
November 16th 13, 01:44 PM
On Saturday, November 16, 2013 5:07:58 AM UTC-5, noel.wade wrote:
>... the LS-4 does _not_ have automatic control hookups.

While earlier LS-4 do not have automatic hook-ups,
late model LS-4s do indeed have automatic hookup.

November 16th 13, 02:43 PM
On Saturday, November 16, 2013 8:44:33 AM UTC-5, Dave Nadler wrote:
> On Saturday, November 16, 2013 5:07:58 AM UTC-5, noel.wade wrote:
>
> >... the LS-4 does _not_ have automatic control hookups.


LS-4 and LS-4a have only automatic hookup for elevator.

LS-4b: all controls are automatic. Also has a tail ballast tank.

Kimmo Hytoenen
November 17th 13, 10:53 PM
We have LS-8a and LS-7WL. I like flying the LS7 more, this far it is
best glider I have been flying what comes to handling. Works well a
little nose heavy, but needs a little more speed while thermaling.
I'm 187 cm and 99,99 kg, and there is not much extra room. This is
the only negative thing in SL-7.
If I would purchase my own glider, I would look something with a
little wider cockpit. We also have ASW-19, that has nicely room.

JS
November 18th 13, 01:55 AM
Owned an LS4 and flown quite a few hours in the 7. Both are very pleasant to fly. The 7 has less cockpit room, but not as tight as Discus/Ventus "A" fuselages.
The 7 has a tilt-up instrument panel which certainly the early 4s didn't (don't know about the b). Believe the winglet mod on the LS7 improved the low speed handling, although I didn't dislike it with original tips. The LS7WL is the only version of the 7 that you can get a 3000-hour life extension for.
As previously noted, LS4 and 4a require 4x L'Hotellier fittings be connected and the LS Sleeve used. The 4b has essentially the same hookups as 6c, 7, 8 and 10.
Must agree the condition, trailer and instruments make a bigger difference.
Jim

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