Kestrel 19 experiences
Marco Haakmeester
take-off and landing behavour, flight evaluation, groundhandling
assembling/disassembling, build quality etc. If possible please
compare to other types like Janus C. Thanks for the trouble.
Marco
Richard Brisbourne
club-owned one in the 1970s.
Sorry, I've never flown a Janus C.
Comments:
General handling and flying:
Rate of roll and handling in thermals are rather better than you might expect
from a 19m glider: the flaps move with the ailerons and rate of roll is
reasonable down to about 45 kt.
Landing performance is the one thing that makes it unsuitable for the
inexperienced. Brakes are not very effective and the high empty weight means
it doesn't want to stop flying and once on the ground it doesn't want to stop
moving. The big wings mean side-slipping is only an option if you know what
you are doing. Good speed control on approach is essential.
You do have a landing parachute, but this is best regarded as an emergency
device for after you have already got the approach wrong. (one tip- if you use
the parachute give the rudder a wiggle as you deploy it- otherwise it tends to
"hang").
Controls and control layout are a bit different: it's the only glider I know
with two flap levers: one, used for general flying droops the ailerons, the
other, used for landing only doesn't. This means that you can land with a lot
of positive flap and still retain good aileron authority. You don't have the
problem you get with many big gliders where you have to go through to negative
flap after touchdown to avoid a ground loop.
The down side of the above is a complicated cockpit layout. The "worst case"
routine for a landing using the brake chute is:
Check flying flap in neutral
Check landing flap position
Lower undercarriage
Check location of parachute jettison (in case needed)
Check location of parachute deploy (for when needed)
Lots of levers.
Rigging
Best summed up as "simple but heavy". I have good rigging kit (dollies,
trestles, etc) and manage with two people. Worst bit is lifting the wing root
up onto the fuselage, but one average strength person can do it if they grit
their teeth a little first. Like all Glasflugel designs it was ahead of its
time on hookups: the ailerons need connecting, everything else is automatic.
Engineering
Generally OK for it's time: there have been one or two mandatory modifications
(notably on the rudder pintle): I have more details if you're interested. One
negative is that the core is balsa rather than foam: if the machine you are
interested in has been wet often this could be a serious problem. I have heard
of other balsa core gliders being written off (notably ASW 15s). My own
machine had the water ballast bags removed in 1980, which I am advised will
probably prolong its life. Unlike modern machines it has a high empty weight
dry, and little extra benefit can be gained from ballast. My own machine has
a maximum landing weight of 450 Kg (and flys at about 440 Kg dry with me in).
I am only allowed a maximum take-off weight of 473 Kg; on a 19m wing the
difference is pretty trivial.
Performance
This is the best bit. Obviously it's not competitive in any unhandicapped
class any more, but for the price you are likely to pay second-hand it's
unbeatable. Because of the high empty weight the weak thermal performance
isn't quite up to the bigger modern ships, but skillfully flown you'll stay
with unballasted standard class machines (and leave them for dead once you
leave the thermal). Interthermal performance in the 70- 80 kt range is very
good: again not quite up to modern machinery flown highly ballasted but most
of the time in British (or Dutch) weather good enough to stay comfortably
ahead of modern 15m machinery and within sight of the 18 m ships. And
remember it cost you about a third of what those guys paid.
Summing up:
Not for beginners
Needs a bit of skill to put down accurately
Needs a strong back (and/or good rigging aids).
Not for top-level competitions (because it's open class)
Performance for price for general cross-country flying exceptionally good.
--
Richard Brisbourne
Soar the big sky
F.L. Whiteley
Richard Brisbourne wrote in message
<946580940...@news.demon.co.uk>...
>On Wed, 29 Dec 1999, Marco Haakmeester wrote:
>>I am interested in flying experiences with this type of glider. E.g.
>>take-off and landing behavour, flight evaluation, groundhandling
>>assembling/disassembling, build quality etc. If possible please
>>compare to other types like Janus C. Thanks for the trouble.
>>
>>Marco
>I've been the sole owner of a Kestrel 19 for two years now, also flew a
>club-owned one in the 1970s.
>
>Sorry, I've never flown a Janus C.
>
seat is a bit like sitting in a wash tub. Goes well, but not as well as a
Kestrel 19.
>Comments:
>General handling and flying:
>Rate of roll and handling in thermals are rather better than you might
expect
>from a 19m glider: the flaps move with the ailerons and rate of roll is
>reasonable down to about 45 kt.
>
With mylar seals top and bottom you can get this down to 38-42kts with +2
setting and good authority. Most UK pilots have cut at notch at 1.5, but
then they mostly use only the internal dacron seals on the flaperons.
>Landing performance is the one thing that makes it unsuitable for the
>inexperienced. Brakes are not very effective and the high empty weight
means
>it doesn't want to stop flying and once on the ground it doesn't want to
stop
>moving. The big wings mean side-slipping is only an option if you know
what
>you are doing. Good speed control on approach is essential.
>
Yes, and the flaps are very powerful and the landing energy high. The Tost
wheel brake is poor. The spoiler/airbrake is aft on the wing chord and
loses effectiveness at higher approach speeds just like the Libelle and SHK.
>You do have a landing parachute, but this is best regarded as an emergency
>device for after you have already got the approach wrong. (one tip- if you
use
>the parachute give the rudder a wiggle as you deploy it- otherwise it tends
to
>"hang").
>
Don't drop it as it will be difficult to replace and expensive even if you
find one.
>Controls and control layout are a bit different: it's the only glider I
know
>with two flap levers: one, used for general flying droops the ailerons, the
>other, used for landing only doesn't. This means that you can land with a
lot
>of positive flap and still retain good aileron authority. You don't have
the
>problem you get with many big gliders where you have to go through to
negative
>flap after touchdown to avoid a ground loop.
>
The inboard flaps may be set to +1 for ground launching and will result in
100m additional height on a 1500m run. Please refer to the POH.
>The down side of the above is a complicated cockpit layout. The "worst
case"
>routine for a landing using the brake chute is:
>Check flying flap in neutral
>Check landing flap position
>Lower undercarriage
>Check location of parachute jettison (in case needed)
>Check location of parachute deploy (for when needed)
>Lots of levers.
>
Yes, and Piggott agrees. You may also want to be sure an overshoot develops
before engaging +2 landing flap. Dumping flap suddenly will result in
significant loss of height if you are coming up short of the mark. +2 is
not needed in any reasonable headwind.
>Rigging
>Best summed up as "simple but heavy". I have good rigging kit (dollies,
>trestles, etc) and manage with two people. Worst bit is lifting the wing
root
>up onto the fuselage, but one average strength person can do it if they
grit
>their teeth a little first. Like all Glasflugel designs it was ahead of
its
>time on hookups: the ailerons need connecting, everything else is
automatic.
>
Easy with three, two is fine, several examples of one-man rigs around. I
think maybe the Kestrel was responsible for the first effective one-person
rig kits. Saw a very nice one at Dunstable in the '70's. You must check
the ailerons connects carefully. It is possible to get appropriate
deflection even when not properly pinned. A positive control check should
reveal this, so do one. You can visually check these as well, have a good
look.
>Engineering
>Generally OK for it's time: there have been one or two mandatory
modifications
>(notably on the rudder pintle): I have more details if you're interested.
One
>negative is that the core is balsa rather than foam: if the machine you are
>interested in has been wet often this could be a serious problem. I have
heard
>of other balsa core gliders being written off (notably ASW 15s). My own
>machine had the water ballast bags removed in 1980, which I am advised will
>probably prolong its life. Unlike modern machines it has a high empty
weight
>dry, and little extra benefit can be gained from ballast. My own machine
has
>a maximum landing weight of 450 Kg (and flys at about 440 Kg dry with me
in).
>I am only allowed a maximum take-off weight of 473 Kg; on a 19m wing the
>difference is pretty trivial.
>
I believe it's recommended to put no water in a Kestrel. One could bag the
tanks, but again, the advantage is not significant. There is only one
lamination of glass on the inner balsa core and pinhole leaks have occurred
on a few.
My inspector placed a small door in the tail wheel well to allow the rudder
inspection without removing the rudder, saving a good hour each annual.
There are four series of Kestrel 19. The series 4 has a significantly
higher empty and all up weight. One series 4 pilot commented to me that his
would spin out of the sky if flown at less than 50 knots in a thermal.
Spins are prohibited. It is non-aerobatic.
>Performance
>This is the best bit. Obviously it's not competitive in any unhandicapped
>class any more, but for the price you are likely to pay second-hand it's
>unbeatable. Because of the high empty weight the weak thermal performance
>isn't quite up to the bigger modern ships, but skillfully flown you'll stay
>with unballasted standard class machines (and leave them for dead once you
>leave the thermal). Interthermal performance in the 70- 80 kt range is
very
>good: again not quite up to modern machinery flown highly ballasted but
most
>of the time in British (or Dutch) weather good enough to stay comfortably
>ahead of modern 15m machinery and within sight of the 18 m ships. And
>remember it cost you about a third of what those guys paid.
>
They rip right along on strong days and into wind performance is very good.
You can turn around and look at the tail and see who's behind you in a
thermal or leeching in a run.
>Summing up:
>Not for beginners
150-250 hours P1 recommended.
>Needs a bit of skill to put down accurately
Yes indeed. Not a good first cross country ship.
>Needs a strong back (and/or good rigging aids).
Gentlemen, hand me my truss. Lighter than LAK wings (barely) Slingsby
added the meter to each wing (Kestrel 17) at the root end. My trailer is
37.5 feet long. Other than that, it rigs like a Libelle, easily. Don't ask
me how I know, but there are 28 laminations of glass on the main carry spar
carry-through.
>Not for top-level competitions (because it's open class)
>Performance for price for general cross-country flying exceptionally good.
>
Kestrel 19's (and their pilots) held a number of records over the years.
Some have been recently broken and a few still stand. The Slingsby root
fillets made a big difference in flow separation over the Kestrel 17.
F. Whiteley
DRBDANIELI
I'ts been some 20 years since we owned our Kestrel 19 but I still remember it
as one of my favorite ships to fly. It was my first glass experience. There
were no glass two seaters at the time and I transitioned into the ship with
about 100 hrs. in a Schweitzer 1-34. I was also a teenage kid at the time. My
only flap experience was some time in a Cessna 150.
While I agree for the most part with the previous post, the Kestrel is an
honest ship but I feel it was a little weak in the rudder by today's standards.
The take off is easy with the nose hook on aero tow and a nice tail wheel to
keep you tracking straight. I prefer to take off with negative flaps for
better airleron control and bring them back to a positive position as speed
builds for flight. I don't recall ever dropping a wing with this ship. We
used to fly at an airport where the wings overhung the landing lights. This
keeps you on your toes!
Flight is really easy once you get used to flying with both hands. I loved the
parallelogram stick and all the comfort features these ships were known for.
Landings were no problem either. The spoilers were effective enough by
themself but the landing flaps really helped. The drag chute was a big bonus.
Personally I would rather land out the Kestrel than a modern standard class
ship. Yes it has mass, wingspan, and a horrible wheelbrake but it has plenty
of tools to get the beast down. I remember landing in a 700' field, over
powerlines, with room to spare.
Think of assembly as basically a big, HEAVY, libelle. My girlfriend and I were
able to do it ourselves and we are normal sized people of average strength.
I also have around 40 hrs. of Janus C time and can tell you that if you fly the
Janus C with no problems, the Kestrel will be a piece of cake. In fact, I
can't think of a more similar glider to check out in first.
We bought our ship new in 1974 and flew it for five years. In that time it had
some rudder flutter problems which the factory worked on by giving us a new
universal joint. Also they designed a reduced weight version with fabric
covering but we never got that far with the modifications. The springs on the
spoilers were weak and the caps would tend to suck up at high speeds and
chatter. After stiffening them up that was no longer a problem. We had some
post cure spar shrinkage problems but that also was fixable with a little
labor.
I managed to get all my diamonds in it and set a bunch of records as a teenage
kid. The Nimbus II and ASW-17 were slightly better in performance when it came
to racing. Personally, I don't feel the Kestrel 19 is quite as good as the
handicap states. Our Kestrel only held 20 gallons of water and even that was
better than nothing. We never had any leaks with the bags and the system was
straight forward. Unlike the previous post, you notice the difference when you
dump it.
All in all, it really was a pleasure to fly and I hope you get as much
enjoyment out of it as I did.
Barry
F.L. Whiteley
>Gentlemen, hand me my truss. Lighter than LAK wings (barely) Slingsby
>added the meter to each wing (Kestrel 17) at the root end.
Minor correction to my previous post, according to Jane's the meter added
was 1/2 at the root and 1/2 at the tip. This is contrary to what I was
told.
I also noted in Barry's post that he could ballast to 20 gals and mentioned
bags. This sounds like a series 4 which has a much higher gross. My gross
was with 90lbs of water, which is less than 10 gals and wing structure was
the tank. So there are differences.
Frank
Richard Brisbourne
[snips]
>While I agree for the most part with the previous post, the Kestrel is an
>honest ship but I feel it was a little weak in the rudder by today's standards.
One thing I forgot to mention- one very popular mod (adopted as standard by the
factory late in the run) was a larger rudder. This is readily recognisable-
it's made from old fashioned sticks and glue instead of the fibreglass used for
the original. This definitely boosts handling in thermals; in fact if you
don't have one and can get one (say from a write-off) it's highly recommended.
I'm trying to relate Frank Whitely's "Series 4" with what I know of the
production history. Mine is a T59F, made in 1974, all fiberglass; although
there's nothing in there now it's obvious from the C of A records it once had
bags in for water. Polystyrene foam to stop the bags chafing on the
inside of the wing are still there. Before its first repair a small pilot might
have got 10 gallons in. I normally thermal around 42 knots, a little faster if
rough. I would imagine it would be very reluctant to spin with +2 thermalling
flap (I've never tried- as Frank says it's not recommended and VNE with
everything hanging is 70Kt.) If you attempt a straight stall with full flap it
will normally just go to mush rather than biting.
There were a very small number (3 or 4?) made at the end of the run with a
carbon spar. This gave both a lower dry weight and a higher max all up, also a
lighter wing for rigging. They still tend to attract a slightly higher price.
F.L. Whiteley
Mike Koerner wrote in message ...
>The interconnection of flaps and ailerons on the Kestrel is so effective
>that in the air you hardly notice you're in an open class ship. However,
the
>larger rudder mentioned previously does seem like a good idea. The yaw
>stability in my ship was minimal. I needed to work the rudder pedals
>constantly to keep the plane going straight at high speed.
>
Mine has the large rudder and it still wanders back and forth when flying
straight. I believe the vertical fin section is so thick that it blanks the
rudder and that separation occurs one side, then the other. I'm hoping to
try improved sealing and zig-zag or dimples to keep the flow laminar on both
sides as it's a bit annoying to keep stabbing the pedals.
Frank
Greg
902 miles in a Kestrel 19. That is only 5 miles less than the world record
of 907 miles.
Mike Koerner <mkoe...@home.com> wrote in message
news:blzb4.27049$ds3.2...@news1.alsv1.occa.home.com...
(By the way, a few of the
> Kestrel 19 records do still stand, at least here in the U.S. :-)
>
> Mike Koerner
>
>
Mike Koerner
regarding Slingsby's 19-meter Kestrel. Perhaps I can add a bit to what's
already been said.
The Kestrel a great sailplane. It's easy to fly and has the performance of
current 15-meter racers at a fraction of the cost. But they won't let you
race with them and its no longer competitive in the open class; so consider
it a just-for-fun or badge and record plane. (By the way, a few of the
Kestrel 19 records do still stand, at least here in the U.S. :-)
The interconnection of flaps and ailerons on the Kestrel is so effective
that in the air you hardly notice you're in an open class ship. However, the
larger rudder mentioned previously does seem like a good idea. The yaw
stability in my ship was minimal. I needed to work the rudder pedals
constantly to keep the plane going straight at high speed.
Also the spoilers were not particularly effective, though the landing flaps
help a lot. And of course, you also have the drag chute, which is
drastically effective.
Deploying the chute haphazardly can be a real problem. If you're trying to
drop into a short field over trees, I'd deploy the chute upon entering
downwind so you can adjust your pattern for the higher descent rate.
Otherwise I'd wait until flair so you're close to the ground when the plane
comes to a stop. Opening the chute just before the trees would be a recipe
for disaster.
Remember too that the drag chute may not work. If the JETTISON handle is
pulled after the chute is installed, it may be unhooked without your knowing
it. When you subsequently pull the DEPLOY handle it will also jettison!
Further, it may be slow to open. If it has remained packed in its rudder
housing for some time, or has gotten wet from rain or from dumping ballast,
then it may not come out instantaneously. As Mr. Brisbourne suggests,
wiggling the rudder as you deploy it will help.
I broke an axle once landing with the drag chute in an alfalfa field. I came
over high-tension lines with the intent of stopping short of some hay bails
which were scattered around the far side of the field. As I flared it
occurred to me that the bails were a bit closer than I expected so I decided
to deploy the chute. I looked down to find the DEPLOY handle and to make
sure I got it and not the similar-looking JETTISON handle; which is also
located at the base of the instrument panel. Apparently I pulled back on the
stick a little as I leaned forward to get the handle. By the time I looked
out of the canopy again I had ballooned up about ten feet, the chute had
deployed and the plane had come to a stop. I felt like a cartoon character
who has just stepped off a cliff; looking around and realizing that I was
about to fall. Between the newly-plowed field, the wheel getting jammed up
sideways in the wheel well and the lack of any appreciable forward speed; my
total rollout was only about nine feet. But there was no serious damage.
Hannes Linke made me a new axle and I was back in the air by the next
weekend.
Another problem I had with the Kestrel was with ground loops. Although these
were certainly caused by pilot error - things like catching the long wings
on bushes - the plane did seem to have a propensity toward coming about if
the tail wasn't right behind the wheel when you touched down. My brother
thought that the main gear might be a bit too far forward. You'll notice
that the tail is quite heavy as the plane sits on the ground.
Anyway, all things considered, the Kestrel 19 is a great plane and great fun
to fly.
Mike Koerner
g oneill
I flew a kestrel 17 for years, virtually the same
aircraft.
I agree with all points re drag chutes but add
one point, when they are wet the chute can spin and spiral
behind you with the water weight and set up a stable
nose up-down pitching movement of about 10-15 degrees
quite alarming at first but speed does not decay and
the chute does not seem to work as well.
Moral :if picketed down outside take your chute pod off and
put in your cockpit .As part of your preflight check feel the
dryness of the fabric.
Mike Koerner <mkoe...@home.com> wrote in message
news:blzb4.27049$ds3.2...@news1.alsv1.occa.home.com...