ASW-19 Maximum Weight

[Ouroboros]

Hello. I'm looking for a sailplane with my partner and we've come across a very nice ASW-19 that we are interested in. The aircraft has a maximum pilot weight of 196 pounds, which my partner just barely squeaks under with a parachute and will probably be over with drinking water and any other baggage. After reviewing the weight and balance documents, we noticed they were using 805 pounds as the max gross weight, but the manual states 899 pounds.

Further digging turned up the type certificate data sheet, which also shows 805 pounds as the maximum weight without water. Does anyone know why the FAA certified the aircraft with a lower max gross weight than stated in the manual? How are other owners dealing with this? If we took the glider experimental, would we be able to use the maximum gross number in the manual instead of the type certificate?

[uncl...@ix.netcom.com]

On Monday, October 15, 2018 at 5:32:29 PM UTC-4, Ouroboros wrote:
> Hello. I'm looking for a sailplane with my partner and we've come across a very nice ASW-19 that we are interested in. The aircraft has a maximum pilot weight of 196 pounds, which my partner just barely squeaks under with a parachute and will probably be over with drinking water and any other baggage. After reviewing the weight and balance documents, we noticed they were using 805 pounds as the max gross weight, but the manual states 899 pounds.
>
> Further digging turned up the type certificate data sheet, which also shows 805 pounds as the maximum weight without water. Does anyone know why the FAA certified the aircraft with a lower max gross weight than stated in the manual? How are other owners dealing with this? If we took the glider experimental, would we be able to use the maximum gross number in the manual instead of the type certificate?

Likely the max pilot weight was determined by the maximum weight of non lifting components.
Operating limitations for production gliders include the same weight and other operating limitations as standard. They are pulled from the flight manual.
UH

[Paul Agnew]

Has the glider had any repairs that upped the empty weight? My ASW19 can take up to 258# pilot and chute, with 10#s of weight in the tail.

The ASW19 is convertible to the 19B with some mods; brake moved to spoiler handle, friction trim, and Tost release support bolts, if my memory serves correctly.

Paul A.
Jupiter, Fl

[infectof...@gmail.com]

The glider did have a gear up landing some time ago. It was also refinished at some point. The new empty weight is 609 pounds.

I'm still not understanding where this 805 number is coming from. Like UH, we initially thought the limit was because of the limit for non lifting parts, but neither of the two weight and balance documents we saw for the aircraft list what the non lifting parts actually weigh. Is it possible to somehow combine the max gross limit and non lifting part limit to come up with 805 pounds? I don't see how it is.

The type certificate data sheet also makes no mention of max weight of non lifting parts. I'm very confused.

Here is a direct link to the type certificate data sheet:
http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgMakeModel.nsf/0/3befadc9f249ca8d8625748e0055f922/$FILE/G36eu.PDF

[Ouroboros]

Oops. Wrong account. That last post was me.

[johnsin...@yahoo.com]

You may do structural damage if you exceed the max wt of non lifting surfaces when flying at or above rough air redline? So, back off on rough air redline! I have done this for years, most G-103's are in this boat,............don't fly it faster than 100 knots!
Flame suit on and ready for all you reg-mangers to shower me with chapter and verse quotes.
JJ

[Dan Daly]

Think of it this way; at 805 lbs, the wing is designed to bend up to a certain amount before it is damaged (or departs). If you add water ballast to go to 900 (ASW-19) or 1000 (ASW-19B) lbs, the weight of that water resists this bending, therefore, you can weigh more before damage occurs. Some gliders, with inner and outer tanks (LS-8 18 comes to mind) the POH/FM specifies which tanks should be filled in the case of partial water loads - presumably for the same reason. I have heard the argument that the incompressible nature of water keeps the tank (and wing) from deforming, adding strength, but looking at open class gliders, the wings do seem to bend!

The difference between max weight with and without water ballast has nothing to do with the max weight of non-lifting parts. That defines the load on the wing attachment to resist the bending. The difference between max weight with and without water just changes the bending of the wing.

BGA data sheet has max weight of non-lifting parts, for your info: https://members.gliding.co.uk/wp-content/uploads/sites/3/2015/04/1430312114_asw19.pdf .

If you have a pilot max weight of 196 lbs you may be wise to do a new weight and balance. There may be some lead in there somewhere...

[Michael Opitz]

I had a -19 for about 5 years from 1978-1983. I was able to convert
it to the B model as Paul mentions and also installed the factory 2 tier
dive brakes. Paul is correct that if you modify it to a B, you will get a
higher max allowable gross weight. It goes from 408 Kg to 454 Kg,
or 898 Lbs to 999 Lbs. See the Schleicher ASW-19 page:
https://www.alexander-schleicher.de/en/flugzeuge/asw-19-
asw-19-b/
If you buy this glider, I suggest you convert it to the B version and
add the 2 tier dive brakes if it doesn't have them as well. The
Germans also have an instrument panel / canopy mod which attaches
the panel to the lift up canopy to make cockpit entry and exit easier.

RO

[2G]

On Monday, October 15, 2018 at 2:32:29 PM UTC-7, Ouroboros wrote:
> Hello. I'm looking for a sailplane with my partner and we've come across a very nice ASW-19 that we are interested in. The aircraft has a maximum pilot weight of 196 pounds, which my partner just barely squeaks under with a parachute and will probably be over with drinking water and any other baggage. After reviewing the weight and balance documents, we noticed they were using 805 pounds as the max gross weight, but the manual states 899 pounds.
>
> Further digging turned up the type certificate data sheet, which also shows 805 pounds as the maximum weight without water. Does anyone know why the FAA certified the aircraft with a lower max gross weight than stated in the manual? How are other owners dealing with this? If we took the glider experimental, would we be able to use the maximum gross number in the manual instead of the type certificate?

Is this a standard category ASW19? If so, you might consider switching to experimental category which would relieve you of the 805 lb limitation (this must be in error, but is probably more trouble than its worth to get it corrected).
BTW, I owned a 19 for many years and was heavier than your partner. It was registered experimental.

Tom

[Ouroboros]

Dan: That makes sense. Thanks. We will definitely be looking for excess weight in the tail. Any idea where one might put such weight?

Michael: I see the TN on Schliechers website, but the TCDS says that the max weight without water is the same for both ASW-19 and ASW-19b, so I don't think that will help me.

Tom: Yes. This glider has a standard certificate. I find it hard to believe that a mistake like that could remain unchanged for so many years!

[2G]

It just might be a typo by the issuing FSDO (805 vs 895).

Tom

[Dan Daly]

From TCDSs for ASW19/ASW19B, EASA max weight dry: 805 lbs for both. Transport Canada max weight dry: 805 lbs for both. BGA max weight dry: 805 lbs for both. With FAA, that would be 8 typos - 4 per 19, 4 per 19B... Therefore, not an FAA typo.

As for where weight might be, from BGA TCDS: "Up to 7 Kg of nose weights may be fitted. 1 Kg of nose weight is equivalent to 2.5 Kg of cockpit weight".

BGA gives weight of non-lifting parts ("everything except wings") as 507 lbs. When you weigh for new CofG, weigh that. It should give an idea of whether repair added a bunch of weight - the fuselage and tail are easy to weigh.

[mdfa...@gmail.com]

Off topic a bit but there is a Pegasus for sale on W&W for a very reasonable price. Depending on who you ask, similar and every bit as nice as a 19 and it likely has a higher max gross. The 3000 hour thing is no longer an issue. If I didn't already have a Peg, I'd be looking very seriously at this one. I'm just sayin'.

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

Quite possibly an estate sale from our club.
Yes, nice ship.
No, not crashed. Separate issue, but worth looking at.

[2G]

Then, WHY does this differ so much from the manufacturer's, Schleicher's, published weights?

Tom

[Darryl Ramm]

On Monday, October 15, 2018 at 2:32:29 PM UTC-7, Ouroboros wrote:

> Hello. I'm looking for a sailplane with my partner and we've come across a very nice ASW-19 that we are interested in. The aircraft has a maximum pilot weight of 196 pounds, which my partner just barely squeaks under with a parachute and will probably be over with drinking water and any other baggage. After reviewing the weight and balance documents, we noticed they were using 805 pounds as the max gross weight, but the manual states 899 pounds.
>
> Further digging turned up the type certificate data sheet, which also shows 805 pounds as the maximum weight without water. Does anyone know why the FAA certified the aircraft with a lower max gross weight than stated in the manual? How are other owners dealing with this? If we took the glider experimental, would we be able to use the maximum gross number in the manual instead of the type certificate?

You don't sat where you or the glider is.

There is a pretty good Schleicher dealer (Williams Soaring) in the USA, call 'em up. If needed pay them to help you with a pre-buy questions and review of the log books etc. if needed. If the aircraft s anywhere near them get a W&B and pre-buy inspection done there.

With any doubt about W&B and past repairs, get a pre-buy W&B as well as inspection done, ideally with future owners in the cockpit.

[Frank Whiteley]

My club once looked into a used ASW-19(B IIRC). Discovered that the original, generous factory stated payload was without instruments. As we went over the glider, we could figure out the weights of the panel, O2, but couldn't figure out the last 10 lb 'gain'. Since our requirement was for a useful pilot/chute load of 235lbs, we passed on the purchase. Interesting to hear about the nose weight option. We missed that, if installed. We figured there may have been 10 lbs of lead in the tail but didn't remove the rudder to check. Nothing in the log books about either. We bought an LS-4a.

Frank

[Paul Agnew]

My ASW19's 10lb tail weight is clearly visible with the horizontal stab off. No need to remove the rudder just to see if weight has been installed.

Paul A.

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

Yes, some ships have an easily removable tail weight, normally top of fin easy to see with horizontal tail off..
There may be weight at the vertical spar not seen without removing the rudder.


As to easy to see/remove tail weight, I am a skinny SOB, I have to eyeball fixed ballast for the craft owner (he has me by maybe 50lbs.....).

[Ouroboros]

I'd also like to know why this 805 pound dry weight limit isn't mentioned in the manual. I've now seen three other weight and balance calculations for ASW-19s and none of them compare dry loaded weights to 805 pounds, even though that would be the limiting factor for their max pilot weights.

Kind of ticks me off that such an important number isn't in the manufacturers documentation.

[uncl...@ix.netcom.com]

On Thursday, October 18, 2018 at 3:56:29 PM UTC-4, Ouroboros wrote:
> I'd also like to know why this 805 pound dry weight limit isn't mentioned in the manual. I've now seen three other weight and balance calculations for ASW-19s and none of them compare dry loaded weights to 805 pounds, even though that would be the limiting factor for their max pilot weights.
>
> Kind of ticks me off that such an important number isn't in the manufacturers documentation.

What does the flight manual say for this configuration?
UH

[Ouroboros]

Here's a link to a copy of the manual:
https://drive.google.com/file/d/1TUVLCNyzEtZrNJtY9p1OPk4AvU4t0ISZ/view?usp=drivesdk

I only see mention of a maximum all up weight and maximum non lifting parts. The manual does have a table for maximum water ballast carried depending on cockpit load, but again is only limited by max gross and non lifting parts.

[uncl...@ix.netcom.com]

The manual(note it is for a 19B) is clear. If you have the weighing info that provides wing weight,in addition to total empty weight, you can determine the max pilot weight for that glider based upon max weight of non lifting components. The manual specifically describes fairly heavy pilot mass in the cockpit.
If it is not a B, there is descriptive info on the Schleicher web site on how to do so. It is not a big deal.
Been There Done That
UH

[uncl...@ix.netcom.com]

Info:
https://www.alexander-schleicher.de/wp-content/uploads/2015/02/190_TM06AB_E.pdf

Raises max mass of pilot to about 254 lb.

UH

[Ouroboros]

That TN doesn't increase the max weight without water, which is the limiting number for this particular glider and the number that is not in the manual.

[Jonathan Walker]

Unless I am missing something all you need to know is the particular
gliders actual (not assumed manufactured) weight of the non-lifting parts.

The max pilot (actually payload, pilot / parachute / ballast weights /
onboard snacks etc) weight is then the lower of:

a) Weight of the actual non-lifting parts subtract from the manuals max
non-lifting parts weight of 230kg (507lbs).
Or
b) 115kg (253.4lbs) which the manuals max pilot weight.
Or
c) The max all up weight less the empty weight (very unlikely to come into
play)

This all assumes that the empty CofG limit is inside the manual
limitations.

The max weight without water is not relevant and most new aircraft don't
list it. You know the max non-lifting parts weight (the critical point due
to bending loads), and the max all up weight inc water
(undercarriage/structural and flight stress loads), then the difference has
to be all in the wings. The aircraft doesn't know if the wings weight is
structure or water so is happy to fly!

[Jonathan Walker]

At 11:52 19 October 2018, Jonathan Walker wrote:
>At 01:37 19 October 2018, Ouroboros wrote:
>>That TN doesn't increase the max weight without water, which is the
>>limiting number for this particular glider and the number that is not in
>>the manual.

------------
Ill try again and see if it still chops off the end of each sentence!!!
------------

[uncl...@ix.netcom.com]

This is a full description of where I was leading. Well stated.
UH

[Dan Marotta]

What about the weight of the horizontal stabilizer?  Given that it
produces negative lift and contributes to the bending loads on the main
spar, is it considered a lifting part or part of the non lifting components?

--
Dan, 5J

[Jonathan Walker]

At 14:31 19 October 2018, Dan Marotta wrote:
>What about the weight of the horizontal stabilizer?  Given that it
>produces negative lift and contributes to the bending loads on the main
>spar, is it considered a lifting part or part of the non lifting
>components?

All except the wings are non-lifting parts in terms of the weight
scheduled.

[Dan Daly]

"Max weight of non lifting components (everything except wings)" - from BGA TCDS. Flight manual is silent on what it is.

From https://members.gliding.co.uk/wp-content/uploads/sites/3/2015/04/1430312108_4-1.pdf , "AMP4-1/Nov 05
BGA AMP Part 4, Leaflet 4-1, Page 1
BGA AIRWORTHINESS AND MAINTENANCE PROCEDURES
PART 4, LEAFLET 4-1
GLIDER WEIGHT AND BALANCE",

"on-Lifting Parts:
"For sailplanes where the Leading Particulars specify a maximum weight
of non-lifting parts, it will additionally be necessary to weigh the wings to enable the weight of the fuselage and tailplane to be calculated; this is the empty weight of non-lifting parts. "

CS-22 doesn't appear to talk about it.

[Ouroboros]

Jonathan: I agree that the max weight without water shouldn't be relevant, but I'm not the one that needs to be convinced. The last two people to do weight and balance for this glider both used the number from the TCDS.

805-609=196 lbs max pilot weight.

How do I convince someone to ignore the number in the TCDS?

[Jonathan Walker]

You need to do the sums and see what the max pilot weight comes out at
first. ie. the max non lifting part less the current non lifting parts. It
may be that comes to 196lbs or have you already done those numbers? Without
this you cannot move forward. It could even be that the max pilot weight is
less than 196lbs!!!!

If the previous paperwork doesn't have the current weight of the non
lifting parts then there would be a suspicion that the calculations haven't
been done correctly. Not uncommon.....

[Dan Marotta]

A simple weighing should put this all to rest.  Two bathroom scales
should get you very close if you don't have access to proper aircraft
scales.

1.  Weigh each wing separately using two bathroom scales.
2.  Weigh the fuselage separately using two bathroom scales, one under
each end of the wing leading edge.
3.  Weigh the horizontal tail separately using one bathroom scale.

The total of the above three is the total empty weight.

With a little juggling of the numbers and a few arithmetic steps you
should easily get your answers.

--
Dan, 5J

[uncl...@ix.netcom.com]

I would start by explaining that the flight manual provided by the builder is the controlling document.
If in doubt, ask Schleicher.
Then I would weigh all the parts and do the sums.
UH

[Dan Daly]

On Friday, October 19, 2018 at 2:46:15 PM UTC-4, Dan Marotta wrote:
> A simple weighing should put this all to rest.  Two bathroom scales
> should get you very close if you don't have access to proper aircraft
> scales.
>
> 1.  Weigh each wing separately using two bathroom scales.
> 2.  Weigh the fuselage separately using two bathroom scales, one under
> each end of the wing leading edge.

> Dan, 5J

I would weigh the fuselage using two scales, one under the main wheel, one under the tail wheel, not under the wing leading edge?

[Dan Marotta]

Yeah, I went back to put in the mention about leading edges and I put it
in the wrong sentence.  My purpose was that, due to the rest of the
content of this thread, I doubt some people understand the whole
concept.  Maybe draw a picture...

--
Dan, 5J

[Ouroboros]

My partner talked to Rex at Williams Soaring today. He told us that, for standard certificate gliders at least, the data in the TCDS takes precedent. So 805 pounds really is the maximum weight of the glider without water. Too bad, as that really limits the useful load of the 19s I've looked at.

[swanso...@yahoo.com]

My favorite donut shop is going to miss me. 😢😢😢

[jpg...@gmail.com]

Why and by whom was that limit introduced? It isn't on the original LBA TCDS for the 19 or 19B as far as I can see from the versions on the BGA website.

[Ouroboros]

I emailed Schliecher about this. Here's the response I received:

"Here are a few short suggestions. The payload of the ASW 19 is 75-115 KG. The weight of the non-lifting parts must not exceed 225 KG.
The maximum take-off weight of 408 kg must not be exceeded with or without water.
Greetings from Poppenhausen"

Sounds to me like they don't know anything about 805 pounds either. In the end, we will probably pass on ASW-19s. 805 pounds limits the maximum pilot weight of them too much and I don't want to risk having to convince someone to willfully ignore the TCDS while doing a weight and balance.

That said, anyone know of a good Discus B for sale in the Western US?

[Paul Agnew]

Is it just me? I must say, in my 36 years as a pilot, I've never searched for the TCDS on any aircraft or rotorcraft I've flown in order to do a W&B calculation. Until the proliferation of the internet, it was nearly impossible to find a TCDS to reference.

The Operating Manual has the weight limits spelled out and includes a W&B diagram for reference. If the FAA decided to make an issue of it, they'd have to challenge themselves for not requiring an Operation Manual change notice to account for the difference between the ops manual and their paperwork.

Get a fresh weighing, don't exceed the manual limits, and have a blast flying the ASW-19.

Paul A.
ASW-19 #193

[Ouroboros]

Funnily enough, the weight and balance was done in 1994, using 805 pounds, by the same person who pointed us to the TCDS recently. I'm not sure where he got the TCDS back then. It was a little before my time. I know the internet was quite widespread at that point, but I can't imagine the FAA had them all up and available that quickly.

[Mike the Strike]

Given that 408 kg is pretty close to 895 pounds, I would support the earlier suggestion of a typo.

Mike

[Charles Longley]

You guys are beating this up too much! I fly an ASW 19 and weigh 225 pounds (not sure what that is in kilos 100ish?). Anyway I strap a parachute to my ass and go flying. The airplane seems to be fine with it. The trim is mid point.