Replacing aging club Grobs...best options?

[allm...@gmail.com]

Hello all! I am trying to gather information on replacement options for my club's aging Grobs. So far I have reached out to SZD for the SZD-54-2 (probably not a factor with no US certification or dealer), the HpH Twin Shark, Shempp-Hirth Duo Discus XL, Schleicher for the ASK-21B and DG for the DG1001 Club Neo.

The club prime purpose for this new glider(s) would be a combination of basic flight training, advanced training (beyond Private) and club member dual cross-country flying. A 40:1 or better best L/D would be preferred, for cross-country training. While many of the options listed are at the upper end of the price range, I need to add more in the lower/middle range.

Any recommendations on other options I have not considered? How are other clubs approaching this common problem? Thanks,

Mark

[Charlie M. (UH & 002 owner/pilot)]

Where are you located...assuming USofA.
ASK-21 has support and I like it. It has longer legs than a 2-33.

[Jon May]

You can't buy a better glider for training than K21b
As a former Duo owner they are beautiful gliders, but not a primary trainer, you would not want to send some one on their first Solo in one.
The K21 is easy to fly and safe for clumsy pilots, but it now has the "B" option which allows the C of G to be moved back for spin training.
In my experience K21 are very tough, and can always be sold on because some one wants one.

[Christoph Barniske]

We did the same evaluation a few years ago, comparing the DG1001 club neo, ASK21B and Perkosz. We ended up buying a new winch instead of a new glider, though.

The costs for all three were basically the same. DG gave us their factory ship with fixed gear for an evaluation weekend and the club members were very pleased with it. The wings were quite light for such a ship and it was easy to rig. But the rudder pedals for the backseat were not adjustable. Flight performance was comparable to an LS4 and it was very silent in the glider during flight. It was not possible to get a Perkosz for testing purpuse. It has been out of production for a while since they changed the factory producing the glider. But it should become available soon.

Our conclusion was, that if you consider a ship for anything else than basic training, the ASK21 is out of the game. The Perkosz and DG1001 club neo have significantly better performance, good flight characteristics and are suitable for spin training.

If basic training is the most important thing for you, the ASK21 might be the better choice, because it is probably the toughest twoseater available. It can take a lot of punishment.

Christoph

[Matthew Scutter]

The ASK21b is probably the best training-only glider ever made - the DG1001 is a great compromise between training and early XC, but slightly too slippery to be a perfect trainer. Never flown a Perkoz.

[Martin Gregorie]

On Mon, 24 May 2021 23:31:12 -0700, Christoph Barniske wrote:

> Our conclusion was, that if you consider a ship for anything else than
> basic training, the ASK21 is out of the game. The Perkosz and DG1001
> club neo have significantly better performance, good flight
> characteristics and are suitable for spin training.
>

Don't believe anybody who says the ASK-21 can't be spun without tail
weights: my pre-solo spin training was done in an ASK-21. Flown off the
winch, thermalled up to safe height and went spinning. It doesn't spin
easily unless the instructor know the magic, absolute minimum energy at
initiation, formula, but it can be spun and recovery is normal. It may or
may not be relevant, but neither that instructor or myself were above
average weight: I normally fly the '21 solo with a parachute, the seat
back in the rear notch and no weights.

I've never flown a 21b so have no idea whether it can also be spun
without tail weight.

> If basic training is the most important thing for you, the ASK21 might
> be the better choice, because it is probably the toughest twoseater
> available. It can take a lot of punishment.
>

Agreed.


--
Martin | martin at
Gregorie | gregorie dot org

[Moshe Braner]

On 5/25/2021 2:31 AM, Christoph Barniske wrote:
> ...
>
> Our conclusion was, that if you consider a ship for anything else than basic training, the ASK21 is out of the game. ...

The ASK-21 (and other gliders of similar performance) can be flown XC
quite well. And perhaps learning to do that is better training than
jumping right into a glider that has higher performance than the first
single seater the student is likely to buy?

See what UH has done in XC mentoring in his ASK21.

I am writing this as somebody who flys XC in a "Russia" AC4 in the NE
US. Similar (or slightly lower) performance to the ASK-21.

[John Foster]

This glass primary trainer niche is a gaping hole in the current market. The only real option available these days for a new glass primary trainer is the ASK-21. However, even used ones are going for $60-70k (they hold their value), but to try to get into one on a budget is nigh-unto impossible. And sailplane manufacturers are businesses, not charities, so they are out to make money. So for those clubs flush with cash/capital, they can afford these nice trainers. However, for the less well-off clubs, they will die out as their trainers deteriorate and the pool of less expensive used glider dries up. While it may not be a huge problem these days, it is going to become more and more of a problem as the fleet of trainers (and instructors) ages out. At least in the US, due to our obesity epidemic, a trainer should have a useful load of 400lbs, or it dramatically limits who you can market soaring to. So many of the Grobs have had damage repaired, which has significantly cut into their useful load. And unless you have a feather-weight instructor, or have a club only of teenage girls, you are going to be quite limited. I wish there were a better solution here, but I just don't see any right now.

[George Haeh]

My club is really lucky to have a 103 with good useful load, and I am getting to really like it as a trainer.

Hint: Toss the lead batteries and replace with a single LiFePO4.

We've been having hull value discussions and I'm thinking next year we should make that enough to get a used ASK-21.

Having de/rigged Perkoz, 21 and 103, they all require considerable manpower.

The DG-1000 is a bit better because of segmented wing and you actually can derig with three. Unfortunately the Club fixed gear version has been rumored not to be amenable to held off landings. The retract versions have a considerably lower gear.

At one club the electric gear was chosen. On one early season flight the instructor was unfamiliar with the emergency gear down system and landed gear up. My suggestion that spring checkouts should include using the emergency gear down fell on deaf ears. With the manual gear, you can get gear collapses. Pick your poison.

One of the nice things about the Grob is that there's no rear spar pins that can disappear.

[Christoph Barniske]

There are basically two gear versions available for the DG1001: 2 wheel and 3 wheel gear. The 2 wheel version is retractable and puts the fuselage in quite a high position over the ground. There is no front wheel. It had a reputation to retract without pilot interaction in the first serial numbers. This is the version being available as an electric gear.

The 3 wheel version is available as fixed and manually retractable variants which can be changed between each other. It is basically the same gear like the DG505. It's quite robust and usually the one that the DG1001 club neo is shipped with. For training purposes, the 3 wheel version is probably the better choice.

[Nick Hill]

On 26/05/2021 05:30, George Haeh wrote:
>
> The DG-1000 is a bit better because of segmented wing and you actually can derig with three. Unfortunately the Club fixed gear version has been rumored not to be amenable to held off landings. The retract versions have a considerably lower gear.
>

The Club fixed gear is lower, as has been said like the DG-505.

My club has a DG-505 and that can need accurate flying for held off
landings.

We did have a 1001 Club on site for a weekend and pilots who were
familiar with the 505 all noted that the approach control on the 1001
Club was uneventful compared to the 505. In fact it was very noticable
that when all levels of club pilot including pre-solo flew it we did not
have a single heavy arrival and most commented how easy it was to do a
nice smooth held off landing.


--

Nick Hill

[Martin Gregorie]

On Wed, 26 May 2021 09:43:14 +0100, Nick Hill wrote:

> We did have a 1001 Club on site for a weekend and pilots who were
> familiar with the 505 all noted that the approach control on the 1001
> Club was uneventful compared to the 505. In fact it was very noticable
> that when all levels of club pilot including pre-solo flew it we did not
> have a single heavy arrival and most commented how easy it was to do a
> nice smooth held off landing.
>

I've only flown a DG-1000 once, but thought it was easy to fly and land,
and very manoeverable one I got used to its size and weight, but getting
in and out of it wasn't easy - rather like an ASH-25.

[Nick Hill]

The DG1001 with the high undercarriage is like that. The Club has an
undercarriage like the K21 and is as easy to get in/out of.

The Club Neo trainer with the new 18m winglets is noticabley improved
handling so not to be compared with the original in terms of behaviour
as a trainer.
--

Nick Hill

[Airport Bum]

Great information here! Anyone out there have experience with and comments on the PW-6?

Cheers,
Jim J6

[metca...@gmail.com]

On Wednesday, 26 May 2021 at 13:02:20 UTC+1, Airport Bum wrote:
> Great information here! Anyone out there have experience with and comments on the PW-6?

I have 254 hours (1417 flights) in a PW6U, all instructing, between 2009 and 2013. All but a couple of flights were from winch launches. The one that I flew was a fairly early model.

It was a very pleasant glider to fly, with light and well-harmonised controls, and no vices. It was very quiet (a blessing when instructing) and pupils liked it too!

The rear cockpit was not large, even for my modest height of 1.8m (5ft11in), and it was easy to have contact between parachute and rearward-hinging rear canopy while climbing in. The rear cockpit was also not well suited for instructing on lengthy flights, as there was no comfortable place to put one's feet when not on the pedals.

It spun (spinned? span?) well on demand, even with pilots near the top of the weight range, which was 110kg (242lb) per seat. Spin recovery was fine, nothing tricky about its spinning behaviour. Demonstration of spin reversal was also straightforward (and quite fun!), unlike any other training 2-seater which I have flown. (Although I _did_ once just manage to demonstrate reversal in a Ka13, to a doubting Thomas. But he was right on the lower weight limit for the front seat.)

Cheers, James.

[AS]

On Monday, May 24, 2021 at 12:56:54 PM UTC-4, allm...@gmail.com wrote:

Mark - if you can lay your hands onto a straight DG500 (18m wing w/o winglets or extensions, retractable gear), I would give it a serious consideration. I flew one of them here in SC for a bit and found it to be a very well behaved and pleasant to fly glider without any bad habits.

Uli
'AS'

[mrop...@gmail.com]

> This glass primary trainer niche is a gaping hole in the current market. The only real option available these days for a new glass primary trainer is the ASK-21. However, even used ones are going for $60-70k (they hold their value), but to try to get into one on a budget is nigh-unto impossible. And sailplane manufacturers are businesses, not charities, so they are out to make money. So for those clubs flush with cash/capital, they can afford these nice trainers. However, for the less well-off clubs, they will die out as their trainers deteriorate and the pool of less expensive used glider dries up. While it may not be a huge problem these days, it is going to become more and more of a problem as the fleet of trainers (and instructors) ages out. At least in the US, due to our obesity epidemic, a trainer should have a useful load of 400lbs, or it dramatically limits who you can market soaring to. So many of the Grobs have had damage repaired, which has significantly cut into their useful load. And unless you have a feather-weight instructor, or have a club only of teenage girls, you are going to be quite limited. I wish there were a better solution here, but I just don't see any right now.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

The lower cost option that you miss is the earlier Grob Twin Astir 1.
They can be had for reasonable prices. Most have around ~4000
hours on them, so plenty of useful life left before the 12,000 hour
limit. The Twin 1 starts with a useful load of ~506 pounds compared
to a Twin II at ~440 or an Acro at ~410. Then take away weight gains
due to repairs, etc. Twin 1's weren't used so much for training, but more
as advanced two seaters for XC. etc, so they usually have less damage
history than Twin II trainers. At 38/1, they glide and climb better than a
Twin II as well. Near "factory level" service is provided by LTB Lindner in
Germany. The controls are a little stiff, (par for 1970's design) but can be
made noticeably more effective through judicious use of Z-tape. There is
no nose wheel, so a tail dolly is required. Due to the main wheel's forward
location, the rear seat pan sits on top of the rear wheel well. This makes for
a more reclined rear pilot position which calls for some jockeying with
cushions, but can be managed. Our club operates 3 Twin 1's, all of which
have little to no damage history and useable payloads of ~500 pounds each.
All 3 together were acquired for less than the price of a single new ASK-21.
It has been our way to bootstrap ourselves up to glass from 2-33's and Blaniks.

www.NutmegSoaring.org

Mike Opitz
RO

[John Foster]

Very nice! Where can these be found? All I've seen advertised has been the Twin II, which are usually pretty beat up, and run between $25-$40K.

[2G]

You can find them on the FAA's aircraft registration database. A make/model search by Grob/Twin Astir shows 6 separate aircraft model codes:
1660211 4
1660202 41
1660201 5
1660501 1
1660301 3
1660309 4
I expect that the code 1660202 is the Twin Astir II, but I don't know what the others are.

Tom

[2G]

Another search turned up this(https://www.federalregister.gov/documents/2004/02/17/04-3354/airworthiness-directives-burkhardt-grob-luft-und-raumfahrt-gmbh-and-co-kg-models-g103-twin-astir):
Models Serial numbers
(1) G103 Twin ASTIR 3000 through 3291.
(2) G103 Twin II 3501 through 3720.
(3) G103 Twin III ACRO All serial numbers beginning with 34101.
(4) G103 C Twin III SL 35002 through 35051.
So by finding the serial number of the glider you can determine the model:
1660211 G103 Twin ASTIR
1660202 G103 Twin II
1660201 G103 Twin ASTIR
1660501 G103 Twin ASTIR
1660311 G103 Twin ASTIR
1660309 G103 Twin ASTIR
There are five different codes for the G103 Twin ASTIR I, so there must be some manufacturing differences between them, and the total number in the US is 17.

Tom

[mrop...@gmail.com]

John, I'm sending you a PM about availability.
RO

[John Foster]

Thanks. So I'm assuming one would need to pursue current owners to see if they would consider selling, as I dont' see any currently for sale on W&W (a number of Twin IIs , but no Twin 1s).

[mrop...@gmail.com]

I have imported to the USA 7 of the 17 referred to by 2G
over the last several years. All, save one, have been sold.
We are working on licensing that last one. There is the
possibility of importing more from Europe, but the market
here has been sort of stagnant in the last couple of years.
No buyers around until a 2-seater gets crashed. Then they
need a replacement and start looking around, only to find
out there's not much available to suit their needs and
pocketbooks. The Blanik L-13 wing spar A.D. created a
vacuum in the lower cost trainer spectrum. Operators have
largely filled that void now, so the market appears close to
equilibrium at present.

Mike Opitz
RO

[AS]

If you are not afraid of dealing with the authorities on both sides of the pond and a shipping broker in between, take a look here: https://www.segelflug.de/osclass/index.php?page=search&sCategory=140
Some trainers there to pick from.

Uli
'AS'

[John Foster]

Yep. Thanks. I was just looking at that. Even in Europe, it seems there is precious little available in glass trainers for under $40k, let alone under $25k. Maybe if we just wait long enough, enough glider pilots will die off or age out, and enough clubs will fold up, and the popularity of soaring will drop enough, that those glass trainers will be so hard to get rid of that the prices will drop (assuming they are not crashed or damaged during this wait). I'm not holding my breath though.

[Christoph Barniske]

The Twin 1 is available with a retractable gear or as a trainer version (fixed gear, no water ballast). The RG version suffers from too large geardoors which are torn off easily in outlandings. Although the gear is fixed, the trainer version also has the box for retracting the gear in the fuselage.

The Twin 1 has slightly better performance than the II (which is already better than the ASK21) and a higher payload. But it's heavy on the controls and the backseat is quite uncomfortable. There's also a noteable lack of control harmony compared to other glass gliders. These are the main reason for their low price. We sold it after a few years and nobody really missed it. In my view, if you get a Twin II with reasonable payload, it's a much better choice.

As for the single-seat Grob gliders, there's also a technical note on applying turbulator tapes on Twin 1 and 2 wings. It improves handling in thermals, but doesn't help with the lack of harmony and stiff controls on the Twin 1.

[mrop...@gmail.com]

The technical note actually allows for turbulator tape in front of
all flight control surfaces. This is separate from the Aero Kurier
article which described under wing turbulator tape to anchor
laminar separation bubbles and improve performance.
Adding Z-Tape to the vertical fin just in front of the rudder actually
makes a very noticeable difference in rudder effectiveness on a
Twin 1. This in turn makes the controls much more harmonized
and in turn more pleasing to fly. People in the USA that have a
Twin II with no damage history and high payload know what they
have and are not selling. I would expect that if a unicorn like that
appeared on the USA market, the asking price would be in the
$50K-$60K range. Most clubs that used to operate L-13 Blaniks
before the wing spar A.D. just don't have that kind of cash
available.

Mike Opitz
RO

[Wallace Berry]

> > 'AS'
> Yep. Thanks. I was just looking at that. Even in Europe, it seems there is precious little available in glass trainers for under $40k, let alone under $25k. Maybe if we just wait long enough, enough glider pilots will die off or age out, and enough clubs will fold up, and the popularity of soaring will drop enough, that those glass trainers will be so hard to get rid of that the prices will drop (assuming they are not crashed or damaged during this wait). I'm not holding my breath though.

As for glass trainers under $40k, Schiebe/Centrair SF-34's often come up for sale on the Segelflug.de site for well under $40k. The few that were built by Schiebe were designated the SF-34 Delphin. The much more numerous Centrair built SF-34 is designated the SF-34 Alliance. Hardly anyone in the U.S. seems to know about them. Only 2 were imported to the U.S. and my club now has both of them, so if you want one, you will have to import it. It's a good looking glider with a reasonably large cockpit and a 485 lb payload, 16.5 meter span. Easy to fly. Thermals well and runs about like the ASK-21. Not quite as rugged as the ASK-21, but is approved for basic aerobatics. The landing gear does not handle heavy side loads well. Original finish on the A model was dull and sort of greyish white. Definitely not up to standards of Grobs and ASK's. Most have been refinished to a better qualityu at this point. The B models had some improvements in that respect and had some other improvements such as a better wheel/brake design. I have no idea about parts availability or support. I think Schiebe has gone out of the aircraft manufacturing business, but some version of Schiebe seems to still exist providing service to the huge number of motorgliders that Schiebe produced. Schiebe produced a few SF-34's in the early 2000's, so I would think they could provide parts still. We have had ours for over 15 years and have never had to buy any parts. Most of the parts that wear, such as in the control linkages appear to be common off-the-shelf aircraft components or are of standard aircraft construction so could be pretty easily reproduced. Tost still lists an improved drum brake wheel and a disc brake wheel for the SF-34.

[son_of_flubber]

On Wednesday, May 26, 2021 at 12:30:03 AM UTC-4, georg...@gmail.com wrote:
> The DG-1000 is .... Unfortunately the Club fixed gear version has been rumored not to be amenable to held off landings.

I had no trouble doing a perfect two-point fully held-off landing. Front seat pilot (me) was 160 + chute. Back seat 180 + chute. I did however slowly open the spoilers as I slowly pulled back on the stick, so maybe that is cheating?