holy smokes YouTube landing

[[email protected]]

http://www.youtube.com/watch?v=HYDdEjloYJ0

Sports Class Nationals people - was this landing as frightening in
person as it is on tape? what was the wind doing then? looks like a
wild ride

[GM]

On Jun 27, 10:20 pm, wrote:
> http://www.youtube.com/watch?v=HYDdEjloYJ0
>
> Sports Class Nationals people - was this landing as frightening in
> person as it is on tape? what was the wind doing then? looks like a
> wild ride


Yes - gusting - yes, it was!

We (the Sports Class Nationals people) were glad when this storm was
over and everybody was accounted for! For a more detailed report, read
the day's report by the CM Richard Holzwarth - it says it all:

http://www.ssa.org/members/contestreports/ContestResultsFullDetail.asp?contestId=&ContestDetailId=3157&ContestName=2007+Sports+Class+Nationals

I landed just a few minutes before the G-2. While approaching the
airport from the east, I went through some pretty rough turbulence and
heavy rain. Others reported also strong turbulence.
Lessons learnt: 1. stay away from t-storms - they are no fun and can
seriously hurt you and your ship! 2. Drain your static system before
the next flight after flying through rain like this - having
completely whacky airspeed indications is no fun either.

Ulrich Neumann
Libelle H301 'GM'

[[email protected]]

On Jun 27, 11:02 pm, GM > wrote:
> On Jun 27, 10:20 pm, wrote:
>
> >http://www.youtube.com/watch?v=HYDdEjloYJ0
>
> > Sports Class Nationals people - was this landing as frightening in
> > person as it is on tape? what was the wind doing then? looks like a
> > wild ride
>
> Yes - gusting - yes, it was!
>
> We (the Sports Class Nationals people) were glad when this storm was
> over and everybody was accounted for! For a more detailed report, read
> the day's report by the CM Richard Holzwarth - it says it all:
>
> http://www.ssa.org/members/contestreports/ContestResultsFullDetail.as...
>
> I landed just a few minutes before the G-2. While approaching the
> airport from the east, I went through some pretty rough turbulence and
> heavy rain. Others reported also strong turbulence.
> Lessons learnt: 1. stay away from t-storms - they are no fun and can
> seriously hurt you and your ship! 2. Drain your static system before
> the next flight after flying through rain like this - having
> completely whacky airspeed indications is no fun either.
>
> Ulrich Neumann
> Libelle H301 'GM'

thanks Ulrich. was hard to tell from the video. what with the
gliders just sitting by the runway not tied down it appeared to me
that the wind wasnt that bad. the G2's didnt appear to be getting
rocked around much which also didn't lead me to think it was that
gusty or turbulent. i suppose there was good sink associated with
rain. seemed he was high and fast. thank goodness he had a strong
glider, i dont think my Cherokee wouldve been able to take that kind
of a beating!

[Mike[_8_]]

Not having a long tailboom helps a lot during a ground loop.

On Jun 28, 10:11 am, wrote:
> On Jun 27, 11:02 pm, GM > wrote:
>
>
>
>
>
> > On Jun 27, 10:20 pm, wrote:
>
> > >http://www.youtube.com/watch?v=HYDdEjloYJ0
>
> > > Sports Class Nationals people - was this landing as frightening in
> > > person as it is on tape? what was the wind doing then? looks like a
> > > wild ride
>
> > Yes - gusting - yes, it was!
>
> > We (the Sports Class Nationals people) were glad when this storm was
> > over and everybody was accounted for! For a more detailed report, read
> > the day's report by the CM Richard Holzwarth - it says it all:
>
> >http://www.ssa.org/members/contestreports/ContestResultsFullDetail.as...
>
> > I landed just a few minutes before the G-2. While approaching the
> > airport from the east, I went through some pretty rough turbulence and
> > heavy rain. Others reported also strong turbulence.
> > Lessons learnt: 1. stay away from t-storms - they are no fun and can
> > seriously hurt you and your ship! 2. Drain your static system before
> > the next flight after flying through rain like this - having
> > completely whacky airspeed indications is no fun eithe

>
> > Ulrich Neumann
> > Libelle H301 'GM'
>
> thanks Ulrich. was hard to tell from the video. what with the
> gliders just sitting by the runway not tied down it appeared to me
> that the wind wasnt that bad. the G2's didnt appear to be getting
> rocked around much which also didn't lead me to think it was that
> gusty or turbulent. i suppose there was good sink associated with
> rain. seemed he was high and fast. thank goodness he had a strong
> glider, i dont think my Cherokee wouldve been able to take that kind
> of a beating!- Hide quoted text -
>
> - Show quoted text -

[Tim Hanke]

I am sitting in the DUO in the photo. We landed 2 minutes before the
G2 in heavy rain. CM was sitting in his glider and we watched the G2
land. The gliders were not tied down beacuse we just landed in the
pouring rain and were waiting for the lightning to stop.

Tim Hanke
Saratoga Springs, NY




On Jun 28, 12:11 pm, wrote:
> On Jun 27, 11:02 pm, GM > wrote:
>
>
>
>
>
> > On Jun 27, 10:20 pm, wrote:
>
> > >http://www.youtube.com/watch?v=HYDdEjloYJ0
>
> > > Sports Class Nationals people - was this landing as frightening in
> > > person as it is on tape? what was the wind doing then? looks like a
> > > wild ride
>
> > Yes - gusting - yes, it was!
>
> > We (the Sports Class Nationals people) were glad when this storm was
> > over and everybody was accounted for! For a more detailed report, read
> > the day's report by the CM Richard Holzwarth - it says it all:
>
> >http://www.ssa.org/members/contestreports/ContestResultsFullDetail.as...
>
> > I landed just a few minutes before the G-2. While approaching the
> > airport from the east, I went through some pretty rough turbulence and
> > heavy rain. Others reported also strong turbulence.
> > Lessons learnt: 1. stay away from t-storms - they are no fun and can
> > seriously hurt you and your ship! 2. Drain your static system before
> > the next flight after flying through rain like this - having
> > completely whacky airspeed indications is no fun either.
>
> > Ulrich Neumann
> > Libelle H301 'GM'
>
> thanks Ulrich. was hard to tell from the video. what with the
> gliders just sitting by the runway not tied down it appeared to me
> that the wind wasnt that bad. the G2's didnt appear to be getting
> rocked around much which also didn't lead me to think it was that
> gusty or turbulent. i suppose there was good sink associated with
> rain. seemed he was high and fast. thank goodness he had a strong
> glider, i dont think my Cherokee wouldve been able to take that kind
> of a beating!- Hide quoted text -
>
> - Show quoted text -

[[email protected]]

Of course Ttim. in fact i had an incredible dream (nightmare?)
earlier this week about sitting in a glider during a severe Tstorm
like this and windjamming through it for fear of getting out and the
glider blowing away.

[st4s03]

He may have had a difficult time seeing level ground to coordinate the
wings.

[Ian]

On 28 Jun, 03:20, wrote:
> http://www.youtube.com/watch?v=HYDdEjloYJ0
>
> Sports Class Nationals people - was this landing as frightening in
> person as it is on tape? what was the wind doing then? looks like a
> wild ride

Coo. I wondered why he didn't put the wheel down until the last
hundred feet, but if he was planning on landing on the wing ...

Ian

[[email protected]]

On Jun 28, 2:57 pm, Ian > wrote:
> On 28 Jun, 03:20, wrote:
>
> >http://www.youtube.com/watch?v=HYDdEjloYJ0
>
> > Sports Class Nationals people - was this landing as frightening in
> > person as it is on tape? what was the wind doing then? looks like a
> > wild ride
>
> Coo. I wondered why he didn't put the wheel down until the last
> hundred feet, but if he was planning on landing on the wing ...
>
> Ian

Thanks for your concern..... Yes, the landing was as frightening in
person as it is on the tape. Much more so. There are several things
that were going on that are not shown on the video. The sink on the
approach to the airport was very heavy. I had been in strong lift
less than 3 minutes before. The CD had been anouncing "light and
variable winds and light rain at the airport". Things changed quite
rapidly. The landing gear was up and the spoilers in because I was
just clearing the shortest trees 1/2 way down the runway. The rain was
pouring down. The visability out of the canopy wasn't very good. And
there was another Genesis on the runway in front of me. I was trying
to turn to the right to avoid messing up two sailplanes. Quite
obviously, I had plenty of energy to pull up a little and complete my
turn before dragging a wing. I am not sure exactly why I wasn't smart
enough to do that..... The wing touched and let me tell you how stupid
I felt while swinging around out of control. Flying near
thunderstorms is stupid. For a few points that day, I flew right under
one. When we got the glider pulled to the side of the runway I had to
sit on the upwind wing for over 10 minutes to protect my Genesis. I
sat there happy to be in one big piece, happy my glider was in one big
piece but mostly feeling stupid......

Don

[[email protected]]

On Jun 28, 7:40 pm, wrote:
> On Jun 28, 2:57 pm, Ian > wrote:
>
> > On 28 Jun, 03:20, wrote:
>
> > >http://www.youtube.com/watch?v=HYDdEjloYJ0
>
> > > Sports Class Nationals people - was this landing as frightening in
> > > person as it is on tape? what was the wind doing then? looks like a
> > > wild ride
>
> > Coo. I wondered why he didn't put the wheel down until the last
> > hundred feet, but if he was planning on landing on the wing ...
>
> > Ian
>
> Thanks for your concern..... Yes, the landing was as frightening in
> person as it is on the tape. Much more so. There are several things
> that were going on that are not shown on the video. The sink on the
> approach to the airport was very heavy. I had been in strong lift
> less than 3 minutes before. The CD had been anouncing "light and
> variable winds and light rain at the airport". Things changed quite
> rapidly. The landing gear was up and the spoilers in because I was
> just clearing the shortest trees 1/2 way down the runway. The rain was
> pouring down. The visability out of the canopy wasn't very good. And
> there was another Genesis on the runway in front of me. I was trying
> to turn to the right to avoid messing up two sailplanes. Quite
> obviously, I had plenty of energy to pull up a little and complete my
> turn before dragging a wing. I am not sure exactly why I wasn't smart
> enough to do that..... The wing touched and let me tell you how stupid
> I felt while swinging around out of control. Flying near
> thunderstorms is stupid. For a few points that day, I flew right under
> one. When we got the glider pulled to the side of the runway I had to
> sit on the upwind wing for over 10 minutes to protect my Genesis. I
> sat there happy to be in one big piece, happy my glider was in one big
> piece but mostly feeling stupid......
>
> Don

well im glad you got it down in one piece Don. sometimes the
pressures of flying work us into making mistakes. this is how we
learn. happy soaring,

[Colin Field[_2_]]

On Jun 28, 7:40 pm, wrote:
>I sat there happy to be in one big piece, happy my
>glider was in one >big piece but mostly feeling stupid......
>
>Don

I suppose the glider would have required an internal
check, expecially of the main spar and wing fixings.
Was there any damage at all, or is the Genesis really
THAT tough?

[[email protected]]

On Jun 29, 2:31 am, Colin Field >
wrote:
> On Jun 28, 7:40 pm, wrote:
>
> >I sat there happy to be in one big piece, happy my
> >glider was in one >big piece but mostly feeling stupid......
>
> >Don
>
> I suppose the glider would have required an internal
> check, expecially of the main spar and wing fixings.
> Was there any damage at all, or is the Genesis really
> THAT tough?


A fairing for the tip spoiler actuator came off during the ground
loop.. It had been held in place with double sided tape. I found it
the next morning on the runway. It was undamaged and got taped back
on. The runway was very wet and slippery. The soil is sandy at CCSC. I
have a feeling that the same landing on a dry hard runway would have
put more loads into the glider. I have lots of experence working on
fiberglass gliders (A&P since 1974) and there was NO structural
damage. The Genesis is built tough. (And Short)

Don

[Shawn[_3_]]

wrote:
> On Jun 29, 2:31 am, Colin Field >
> wrote:
>> On Jun 28, 7:40 pm, wrote:
>>
>>> I sat there happy to be in one big piece, happy my
>>> glider was in one >big piece but mostly feeling stupid......
>>> Don
>> I suppose the glider would have required an internal
>> check, expecially of the main spar and wing fixings.
>> Was there any damage at all, or is the Genesis really
>> THAT tough?
>
>
> A fairing for the tip spoiler actuator came off during the ground
> loop.. It had been held in place with double sided tape. I found it
> the next morning on the runway. It was undamaged and got taped back
> on. The runway was very wet and slippery. The soil is sandy at CCSC. I
> have a feeling that the same landing on a dry hard runway would have
> put more loads into the glider. I have lots of experence working on
> fiberglass gliders (A&P since 1974) and there was NO structural
> damage. The Genesis is built tough. (And Short)


Don,

Good deal :-)
Thanks for sharing your inside-the-cockpit analysis.
I've had a couple landings in really hairy conditions, and I agree with
you, best to avoid T-storms!



Shawn

[[email protected]]

On Jun 29, 7:45?am, wrote:
> On Jun 29, 2:31 am, Colin Field >
> wrote:
>
> > On Jun 28, 7:40 pm, wrote:
>
> > >I sat there happy to be in one big piece, happy my
> > >glider was in one >big piece but mostly feeling stupid......
>
> > >Don
>
> > I suppose the glider would have required an internal
> > check, expecially of the main spar and wing fixings.
> > Was there any damage at all, or is the Genesis really
> > THAT tough?
>
> A fairing for the tip spoiler actuator came off during the ground
> loop.. It had been held in place with double sided tape. I found it
> the next morning on the runway. It was undamaged and got taped back
> on. The runway was very wet and slippery. The soil is sandy at CCSC. I
> have a feeling that the same landing on a dry hard runway would have
> put more loads into the glider. I have lots of experence working on
> fiberglass gliders (A&P since 1974) and there was NO structural
> damage. The Genesis is built tough. (And Short)
>
> Don

Don,

I was standing by the gate down where you landed and remembered
thinking we were watching a beautiful plane getteing torn up.....and
being amazed when everything held together and the canopy came up. I
don't remember seeing the gear touch until you were facing back up the
field. Great job of flying on your part with gusts, sheeting rain,
massive lightning, planes in front, behind and besides. Then joking
with you out on the grid Monday when you found the fairing. You
certainly earned the Lime Crew's nickname for your plane that day
("Donkey Kong"). Probably one of the most exciting days I can think
of at the "Creek". As we say here in Kentucky "Ya done good, boy".

Gary Adams

[Bill Daniels]

That no damage resulted to the Genesis will come as no surprise to those
familiar with Jim Marske's simular designs. These are all very strong
gliders. The strength comes mainly from the shape and not from robust
structure although the Genesis is, in fact, very robust.

It's interesting to ask whether the 1-26 with its well respected out landing
capability would have done as well. Certainly, Genesis owners have less
reason to fear out landings than the typical glider owner with a fragile
tailboom.

I think this incident may have an influence on future designs. The Genesis
obtains excellent handling and quite respectable performance without a tail
boom which forces the question, " Why have one?" The 18 meter and larger
gliders would obtain even greater relative performance and damage resistance
since the fuselage size need not increase in porportion to wing span. I
wonder what the ETA would be like with the Genesis fuselage.

Bill Daniels


> wrote in message
oups.com...
> On Jun 29, 2:31 am, Colin Field >
> wrote:
>> On Jun 28, 7:40 pm, wrote:
>>
>> >I sat there happy to be in one big piece, happy my
>> >glider was in one >big piece but mostly feeling stupid......
>>
>> >Don
>>
>> I suppose the glider would have required an internal
>> check, expecially of the main spar and wing fixings.
>> Was there any damage at all, or is the Genesis really
>> THAT tough?
>
>
> A fairing for the tip spoiler actuator came off during the ground
> loop.. It had been held in place with double sided tape. I found it
> the next morning on the runway. It was undamaged and got taped back
> on. The runway was very wet and slippery. The soil is sandy at CCSC. I
> have a feeling that the same landing on a dry hard runway would have
> put more loads into the glider. I have lots of experence working on
> fiberglass gliders (A&P since 1974) and there was NO structural
> damage. The Genesis is built tough. (And Short)
>
> Don
>

[Ray Lovinggood]

At 18:30 03 July 2007, Bill Daniels wrote:
>That no damage resulted to the Genesis will come as
>no surprise to those
>familiar with Jim Marske's simular designs. These
>are all very strong
>gliders. The strength comes mainly from the shape
>and not from robust
>structure although the Genesis is, in fact, very robust.
>
>It's interesting to ask whether the 1-26 with its well
>respected out landing
>capability would have done as well. Certainly, Genesis
>owners have less
>reason to fear out landings than the typical glider
>owner with a fragile
>tailboom.
>
>I think this incident may have an influence on future
>designs. The Genesis
>obtains excellent handling and quite respectable performance
>without a tail
>boom which forces the question, ' Why have one?' The
>18 meter and larger
>gliders would obtain even greater relative performance
>and damage resistance
>since the fuselage size need not increase in porportion
>to wing span. I
>wonder what the ETA would be like with the Genesis
>fuselage.
>
>Bill Daniels


Bill,

I have no idea how an ETA type wingspan would work
on a Genesis type fuselage, but I can picture the amount
of storage space one would gain in the trailer!

And yes, I was impressed with the video. It's the
first, and I hope the last time I've ever seen a ground
loop. And I'm impressed the Genesis came through basically
unhurt.

Nicely done, Jim Marske!

Ray Lovinggood
Carrboro, North Carolina, USA

[Paul Hanson]

>I wonder what the ETA would be like with the Genesis
>fuselage.
>
>Bill Daniels

It would probably then be able to withstand the mandatory
spin test for one thing! ;-)

Paul Hanson
"Do the usual, unusually well"--Len Niemi

[Steve Davis]

>>The strength comes mainly from the shape
>>and not from robust structure although the
>>Genesis is, in fact, very robust.
>>Bill Daniels

>Bill,
>I have no idea how an ETA type wingspan would work
>on a Genesis type fuselage, but I can picture the amount
>of storage space one would gain in the trailer!

There was talk of a garage-able Genesis although
it never got beyond the 'what if' stage. Since the
fuselage is only 14.25 ft. long, with two-piece wings
it could fit. With elevators on the wing instead of
a T-tail, the vertical stab. could probably have a
removable section, simplifying the trailer.

>And yes, I was impressed with the video. It's the
>first, and I hope the last time I've ever seen a ground
>loop. And I'm impressed the Genesis came through basically
>unhurt.
>
>Nicely done, Jim Marske!

And Robert Mudd and engineers from Sportine
Aviacija. Robert mentioned in the Genesis Yahoo
Group that SA engineers had added gussets to the
MLG wheel box assembly. Those gussets got tested
and they passed.

>Ray Lovinggood
>Carrboro, North Carolina, USA

[Colin Field[_2_]]

> I wonder what the ETA would be like with the Genesis
>fuselage.

Maybe a bit like this...

http://tinyurl.com/yuqb7v

[Paul Remde]

Funny! Well done.

Paul Remde

"Colin Field" > wrote in message
...
>> I wonder what the ETA would be like with the Genesis
>>fuselage.
>
> Maybe a bit like this...
>
> http://tinyurl.com/yuqb7v
>
>
>
>

[Eric Greenwell]

Bill Daniels wrote:
> I think this incident may have an influence on future designs. The
Genesis
> obtains excellent handling and quite respectable performance without a tail
> boom which forces the question, " Why have one?" The 18 meter and larger
> gliders would obtain even greater relative performance and damage resistance
> since the fuselage size need not increase in porportion to wing span.

I suspect the increase in wing span might still require a commensurate
increase in rudder/fin and boom length, just to control yaw, even it
wasn't needed for the elevator. Also, flapped gliders have relatively
less drag from the elevator than aileron-only gliders, so I think they
would have still be better off because the wing could be more easily
optimized for performance.

> I
> wonder what the ETA would be like with the Genesis fuselage.

A further complication with the ETA is controlling the glider under
power. I have no idea how it would work out in practice, but I'm
guessing any advantages of the Genesis type design would be lessened by
the control requirements under power. Add in the problems of stabilizing
a floppy, high-aspect ratio wing, and I'm willing to believe the nod for
performance still goes to the conventional tail.

--
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

[Bill Daniels]

Just idle fun speculation, of course. Clearly, a conventional rudder like
the Genesis wouldn't work with a 31 meter span. But, it would take only a
tiny amount of drag at the wing tip acting through a 15 meter moment arm to
produce huge yaw moments. I've run this calculation a few times and the net
drag of tip drag rudders would acutally be less than a conventional rudder.
A trailing edge elevator would work fine regardless of the span. The
Genesis "T" tail is actually a hinderance.

As for the control moments to control engine thrust and "P" factors, yes,
that is a challenge. A few prople have suggested lowering the thrust line
so it passes through the CG and aerodynamic center. The rear propeler could
fold back somewhat like a Carat and be pulled into a tube in the rear
fuselage. Not sure how the landing gear would work with a low thrust line.

Obviously there would be some weight reduction to the 'non lifting parts'
that would roll through the wing spar calculations allowing a lighter wing.
Probably not a huge weight reduction but every bit helps the wing bending
moment.

Turning flight might be easier. The short fuselage could be kept aligned
with the local airflow easier than the very long one of the ETA.

Obviously, something like this isn't a 'cut and paste' sort of design. Each
aspect of the design would break new ground and have to be carefully thought
through. Each design change would affect everything else.

Bill Daniels


"Eric Greenwell" > wrote in message
news:nmkji.6642$wu5.6324@trndny03...
> Bill Daniels wrote:
> > I think this incident may have an influence on future designs. The
> Genesis
>> obtains excellent handling and quite respectable performance without a
>> tail boom which forces the question, " Why have one?" The 18 meter and
>> larger gliders would obtain even greater relative performance and damage
>> resistance since the fuselage size need not increase in porportion to
>> wing span.
>
> I suspect the increase in wing span might still require a commensurate
> increase in rudder/fin and boom length, just to control yaw, even it
> wasn't needed for the elevator. Also, flapped gliders have relatively less
> drag from the elevator than aileron-only gliders, so I think they would
> have still be better off because the wing could be more easily optimized
> for performance.
>
>> I wonder what the ETA would be like with the Genesis fuselage.
>
> A further complication with the ETA is controlling the glider under power.
> I have no idea how it would work out in practice, but I'm guessing any
> advantages of the Genesis type design would be lessened by the control
> requirements under power. Add in the problems of stabilizing a floppy,
> high-aspect ratio wing, and I'm willing to believe the nod for performance
> still goes to the conventional tail.
>
> --
> 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

[bumper]

"Bill Daniels" <bildan@comcast-dot-net> wrote in message
. ..

(really important stuff snipped)

The
> Genesis "T" tail is actually a hinderance.
> Bill Daniels
>



I bet not nearly the "hindrance" as would occur if you attempt to fly the
Genesis without that horizontal stab.

bumper
"Dare to be different . . . circle in sink"
QV and MKII

[[email protected]]

On Jul 6, 8:56 am, "Bill Daniels" <bildan@comcast-dot-net> wrote:
> Just idle fun speculation, of course. Clearly, a conventional rudder like
> the Genesis wouldn't work with a 31 meter span. But, it would take only a
> tiny amount of drag at the wing tip acting through a 15 meter moment arm to
> produce huge yaw moments. I've run this calculation a few times and the net
> drag of tip drag rudders would acutally be less than a conventional rudder.
> A trailing edge elevator would work fine regardless of the span. The
> Genesis "T" tail is actually a hinderance.
>
> As for the control moments to control engine thrust and "P" factors, yes,
> that is a challenge. A few prople have suggested lowering the thrust line
> so it passes through the CG and aerodynamic center. The rear propeler could
> fold back somewhat like a Carat and be pulled into a tube in the rear
> fuselage. Not sure how the landing gear would work with a low thrust line.
>
> Obviously there would be some weight reduction to the 'non lifting parts'
> that would roll through the wing spar calculations allowing a lighter wing.
> Probably not a huge weight reduction but every bit helps the wing bending
> moment.
>
> Turning flight might be easier. The short fuselage could be kept aligned
> with the local airflow easier than the very long one of the ETA.
>
> Obviously, something like this isn't a 'cut and paste' sort of design. Each
> aspect of the design would break new ground and have to be carefully thought
> through. Each design change would affect everything else.
>
> Bill Daniels
>
> "Eric Greenwell" > wrote in message
>
> news:nmkji.6642$wu5.6324@trndny03...
>
>
>
> > Bill Daniels wrote:
> > > I think this incident may have an influence on future designs. The
> > Genesis
> >> obtains excellent handling and quite respectable performance without a
> >> tail boom which forces the question, " Why have one?" The 18 meter and
> >> larger gliders would obtain even greater relative performance and damage
> >> resistance since the fuselage size need not increase in porportion to
> >> wing span.
>
> > I suspect the increase in wing span might still require a commensurate
> > increase in rudder/fin and boom length, just to control yaw, even it
> > wasn't needed for the elevator. Also, flapped gliders have relatively less
> > drag from the elevator than aileron-only gliders, so I think they would
> > have still be better off because the wing could be more easily optimized
> > for performance.
>
> >> I wonder what the ETA would be like with the Genesis fuselage.
>
> > A further complication with the ETA is controlling the glider under power.
> > I have no idea how it would work out in practice, but I'm guessing any
> > advantages of the Genesis type design would be lessened by the control
> > requirements under power. Add in the problems of stabilizing a floppy,
> > high-aspect ratio wing, and I'm willing to believe the nod for performance
> > still goes to the conventional tail.
>
> > --
> > 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" atwww.motorglider.org- Hide quoted text -
>
> - Show quoted text -

Bill,

Didnt one of the early flying wings use this for yaw control? small
spoilers at the tip of the wings. im imagining a long wing with a pod
on front and a boom back to just an elevator. sure would look cool

[Bill Daniels]

"bumper" > wrote in message
...
>
> "Bill Daniels" <bildan@comcast-dot-net> wrote in message
> . ..
>
> (really important stuff snipped)
>
> The
>> Genesis "T" tail is actually a hinderance.
>> Bill Daniels
>>
>
>
>
> I bet not nearly the "hindrance" as would occur if you attempt to fly the
> Genesis without that horizontal stab.
>
> bumper
> "Dare to be different . . . circle in sink"
> QV and MKII
>
Of course, an existing Genesis won't fly without the tail. But the Genesis
CONCEPT could have as evidenced by Jim Marske's designs.

Bill Daniels

[Bill Daniels]

> wrote in message
ups.com...
> On Jul 6, 8:56 am, "Bill Daniels" <bildan@comcast-dot-net> wrote:
>> Just idle fun speculation, of course. Clearly, a conventional rudder
>> like
>> the Genesis wouldn't work with a 31 meter span. But, it would take only
>> a
>> tiny amount of drag at the wing tip acting through a 15 meter moment arm
>> to
>> produce huge yaw moments. I've run this calculation a few times and the
>> net
>> drag of tip drag rudders would acutally be less than a conventional
>> rudder.
>> A trailing edge elevator would work fine regardless of the span. The
>> Genesis "T" tail is actually a hinderance.
>>
>> As for the control moments to control engine thrust and "P" factors, yes,
>> that is a challenge. A few prople have suggested lowering the thrust
>> line
>> so it passes through the CG and aerodynamic center. The rear propeler
>> could
>> fold back somewhat like a Carat and be pulled into a tube in the rear
>> fuselage. Not sure how the landing gear would work with a low thrust
>> line.
>>
>> Obviously there would be some weight reduction to the 'non lifting parts'
>> that would roll through the wing spar calculations allowing a lighter
>> wing.
>> Probably not a huge weight reduction but every bit helps the wing bending
>> moment.
>>
>> Turning flight might be easier. The short fuselage could be kept aligned
>> with the local airflow easier than the very long one of the ETA.
>>
>> Obviously, something like this isn't a 'cut and paste' sort of design.
>> Each
>> aspect of the design would break new ground and have to be carefully
>> thought
>> through. Each design change would affect everything else.
>>
>> Bill Daniels
>>
>> "Eric Greenwell" > wrote in message
>>
>> news:nmkji.6642$wu5.6324@trndny03...
>>
>>
>>
>> > Bill Daniels wrote:
>> > > I think this incident may have an influence on future designs. The
>> > Genesis
>> >> obtains excellent handling and quite respectable performance without
>> >> a
>> >> tail boom which forces the question, " Why have one?" The 18 meter
>> >> and
>> >> larger gliders would obtain even greater relative performance and
>> >> damage
>> >> resistance since the fuselage size need not increase in porportion to
>> >> wing span.
>>
>> > I suspect the increase in wing span might still require a commensurate
>> > increase in rudder/fin and boom length, just to control yaw, even it
>> > wasn't needed for the elevator. Also, flapped gliders have relatively
>> > less
>> > drag from the elevator than aileron-only gliders, so I think they would
>> > have still be better off because the wing could be more easily
>> > optimized
>> > for performance.
>>
>> >> I wonder what the ETA would be like with the Genesis fuselage.
>>
>> > A further complication with the ETA is controlling the glider under
>> > power.
>> > I have no idea how it would work out in practice, but I'm guessing any
>> > advantages of the Genesis type design would be lessened by the control
>> > requirements under power. Add in the problems of stabilizing a floppy,
>> > high-aspect ratio wing, and I'm willing to believe the nod for
>> > performance
>> > still goes to the conventional tail.
>>
>> > --
>> > 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"
>> > atwww.motorglider.org- Hide quoted text -
>>
>> - Show quoted text -
>
> Bill,
>
> Didnt one of the early flying wings use this for yaw control? small
> spoilers at the tip of the wings. im imagining a long wing with a pod
> on front and a boom back to just an elevator. sure would look cool

Most flying wings use some sort of wing tip drag rudder. The Genesis uses
"flippers" that move upwards at twice the rate of the ailerons. The B2 uses
split trailing edge drag rudders.

The stabilizer/elevator doesn't need the long boom at all. Placing the
elevators on the inboard wing trailing edge works very well.

Bill Daniels

[Eric Greenwell]

Bill Daniels wrote:
> Just idle fun speculation, of course. Clearly, a conventional rudder like
> the Genesis wouldn't work with a 31 meter span. But, it would take only a
> tiny amount of drag at the wing tip acting through a 15 meter moment arm to
> produce huge yaw moments. I've run this calculation a few times and the net
> drag of tip drag rudders would acutally be less than a conventional rudder.
> A trailing edge elevator would work fine regardless of the span. The
> Genesis "T" tail is actually a hinderance.

Now a portion of the wing is not working at the optimum flap setting. I
think that the drag would be significant. The Genesis optimization
problem is quite different, as is a conventional Standard Class glider
optimization compared to a 15 Meter class glider. Note how different the
wing designs tend to be for Standard vs 15 Meter gliders (generally
lower aspect ratio/larger area for the Standard class).

>
> As for the control moments to control engine thrust and "P" factors, yes,
> that is a challenge. A few prople have suggested lowering the thrust line
> so it passes through the CG and aerodynamic center. The rear propeler could
> fold back somewhat like a Carat and be pulled into a tube in the rear
> fuselage. Not sure how the landing gear would work with a low thrust line.

Perhaps using a jet would make the problem much easier; at least, the
thrust could be closer to the center line.

--
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

[bumper]

"Bill Daniels" <bildan@comcast-dot-net> wrote in message
. ..
>>
> Of course, an existing Genesis won't fly without the tail. But the
> Genesis CONCEPT could have as evidenced by Jim Marske's designs.
>
> Bill Daniels
>

Would the resulting aircraft perform better than the much more numerous and
seemingly more successful "standard" planform?

While I admire experimenting and innovation, I wonder why, if the flying
wing concept were so good, at least as applied to gliders, hasn't it been
embraced by major manufacturers? They seem willing to go to great lengths to
eek out as much performance as they can. Could it be that the tweaks needed
to impart longitudinal stability, like reflexed trailing edges, are not
efficient enough over a broad enough speed range?

bumper
Minden, NV

[Bruce]

Master Bumper

You are indeed correct. The Akavlieg Braunschweig tried this with the quite
radical SB13 prototype. This Standard-Class glider first flew in 1988. Lots of
details in Dr Fred Thomas' "Fundamentals of Sailplane Design.
15m wingspan, 15 degree sweep, elevons and winglets doubling as vertical
stabilisers. Differential deflection of rudders on the winglets to counter yaw.

It proved to have similar performance to contemporary standard class
gliders.Some advantage in efficiency being generally lost to handling induced
inefficiency. So - There was no compelling efficiency advantage. Conversely
there were substantial operational and controllability issues and high pilot
work load. etc...

For example; It proved impossible to winch launch safely. Apparently
Braunschweig has used the SB13 in contests, and also allows experienced akavlieg
pilots to fly it. There are quotes like "it exhibits very poor flying and
handling qualities in turbulent conditions." It is the subject of at least one
thesis on aeroelastic properties.

Details at:

http://www.akaflieg-braunschweig.de/prototypen/sb13/

And here -

http://www.sailplanedirectory.com/braunsch.htm#SB-13

The Genesis is a more modern design, and presumably learned from the
difficulties they had with the SB13 - which was after all a prototype designed
to investigate innovation, rather than a commercial endeavor.

There have been others with a similar idea, in fact the SB13 was not the first I
know of at improving on the Horten - the BKB1 has that honour. Although the
information is unsubstantiated - there is some info here
http://www.astercity.net/~krisabc/BKB/Brochocki3-en.html

Maybe Jim Marske will develop a giant killer from this concept - but I
personally can't see it happening. It is a fascinating concept -and so we keep
trying to minimise the tail boom (cf Diana 2) But it remains the best way to do
things. Consider - Even Burt Rutan eventually went back to the conventional
layout with the Global Flyer (http://www.scaled.com/projects/globalflyer.html) -
it is not conventional for nothing - it represents the best compromise.

My 2 (South African ) cents worth - not that that means much at ZAR 7 / USD but
there you have it.

bumper wrote:
> "Bill Daniels" <bildan@comcast-dot-net> wrote in message
> . ..
>> Of course, an existing Genesis won't fly without the tail. But the
>> Genesis CONCEPT could have as evidenced by Jim Marske's designs.
>>
>> Bill Daniels
>>
>
> Would the resulting aircraft perform better than the much more numerous and
> seemingly more successful "standard" planform?
>
> While I admire experimenting and innovation, I wonder why, if the flying
> wing concept were so good, at least as applied to gliders, hasn't it been
> embraced by major manufacturers? They seem willing to go to great lengths to
> eek out as much performance as they can. Could it be that the tweaks needed
> to impart longitudinal stability, like reflexed trailing edges, are not
> efficient enough over a broad enough speed range?
>
> bumper
> Minden, NV
>
>
>
>
>

[Bill Daniels]

"bumper" > wrote in message
...
>
> "Bill Daniels" <bildan@comcast-dot-net> wrote in message
> . ..
>>>
>> Of course, an existing Genesis won't fly without the tail. But the
>> Genesis CONCEPT could have as evidenced by Jim Marske's designs.
>>
>> Bill Daniels
>>
>
> Would the resulting aircraft perform better than the much more numerous
> and seemingly more successful "standard" planform?
>
> While I admire experimenting and innovation, I wonder why, if the flying
> wing concept were so good, at least as applied to gliders, hasn't it been
> embraced by major manufacturers? They seem willing to go to great lengths
> to eek out as much performance as they can. Could it be that the tweaks
> needed to impart longitudinal stability, like reflexed trailing edges, are
> not efficient enough over a broad enough speed range?
>
> bumper
> Minden, NV
>
The answer to your questions is that we really don't know. There are good
people on both sides of the arguement.

The thing with all flying wings both the swept variety and the straight or
slightly swept forward is that there isn't the long history of incremental
development. Designers have found it expedient to just keep tweaking the
conventional tailboom design to get another small increment of performance.
This has led to a huge body of knowledge about that approach. The body of
knowledge about flying wings is far smaller thus the development risks are
much higher.

There are two things that might change that. First, there just doesn't seem
to be much more performance to extract out of the conventional approach so
designers may start taking risks with more radical approaches. Second, the
state of Computational Fluid Dynamics (CFD) has reached the point where it
can reduce the risks of a radical design.

Another problem with the history of flying wing designs is that the typical
pilot doesn't understand the subtile details of what makes a flying wing
work well. If a particular flying wing design doesn't turn out to be a
world beater due to some small fixable detail. The general response will be
to condem the whole flying wing idea. This has discouraged a lot of
designers from even trying.

Still, the lure is there. In any reasonable comparison, the flying wing
will have lower parasitic drag and the overall structure will be more
robust. That inherent robustness is like money in the bank to a designer.
He can spend it on things like smoother skins, higher Va speeds or lighter
wings panels.

The advantage to most of us, should the designer begin to try flying wings,
is that it would be an exciting thing to see after all these years of
look-alike pod and boom designs.

Bill Daniels

[bumper]

"Bill Daniels" <bildan@comcast-dot-net> wrote in message
. ..
> The advantage to most of us, should the designer begin to try flying
> wings, is that it would be an exciting thing to see after all these years
> of look-alike pod and boom designs.
>
> Bill Daniels
>

Which most are you referring to? I haven't seen a flying wing that
approaches the grace and beauty of some of the current designs which are
just about the prettiest things flying . . . right after some of the
feathered critters.

bumper
ASH26E - - pod, boom, and gorgeous
Minden NV

[Tony Verhulst]

> It proved to have similar performance to contemporary standard class
> gliders.Some advantage in efficiency being generally lost to handling
> induced inefficiency. So - There was no compelling efficiency
> advantage.

It should be noted that most all hang gliders are flying wings. The
reason for this has more to do with portability than with performance.
The handling quality of many hang gliders since, say the early '80, are
quite pleasant - remember, this is weight shift contol.

Tony V

[Steve Davis]

At 17:42 06 July 2007, Bumper wrote:
>
>'Bill Daniels' wrote in message
>(really important stuff snipped)

> The Genesis 'T' tail is actually a hindrance.
> Bill Daniels

>I bet not nearly the 'hindrance' as would occur if
>you attempt to fly the
>Genesis without that horizontal stab.
>
>bumper

I don't agree that the Genesis elevator on the tail
is a hindrance.
Like everything else in engineering it is a trade off.
Putting the
all-flying elevator on a 'T' tail keeps it out of ground
effect so the
control feel is the same during landing as during flight.
The moment
arm of the Genesis elevator allowed the designers to
move the
cockpit forward so the pilots head is in front of the
wing leading
edge giving much better visibility than would occur
if the pilot has to
sit on the cg. The chord at the wing root on the Genesis
is quite
large but the trailing edge is just as robust as the
rest of the glider
so handling the 140 Lb. wing isn't a problem.
With a large elevator at the trailing edge there could
be an
assembly/disassembly issue. Would it be separately
removable
or fixed to the wing? The elevator on the Genesis
weighs less than
10 Lbs. and is short enough that you can stick it under
your arm or
carry it off with one hand. The Genesis has a cockpit
large enough
for a 6'10' 255 Lb. pilot to move around in. I think
just the size of
it is as great a 'hindrance' to performance as any
other trade off.

[Nyal Williams]

6'10'? 255lbs? What are the load limits for this
glider?

At 05:12 11 July 2007, Steve Davis wrote:
>At 17:42 06 July 2007, Bumper wrote:
>>
>>'Bill Daniels' wrote in message
>>(really important stuff snipped)
>
>> The Genesis 'T' tail is actually a hindrance.
>> Bill Daniels
>
>>I bet not nearly the 'hindrance' as would occur if
>>you attempt to fly the
>>Genesis without that horizontal stab.
>>
>>bumper
>
>I don't agree that the Genesis elevator on the tail
>is a hindrance.
>Like everything else in engineering it is a trade off.
> Putting the
>all-flying elevator on a 'T' tail keeps it out of ground
>effect so the
>control feel is the same during landing as during flight.
> The moment
>arm of the Genesis elevator allowed the designers to
>move the
>cockpit forward so the pilots head is in front of the
>wing leading
>edge giving much better visibility than would occur
>if the pilot has to
>sit on the cg. The chord at the wing root on the Genesis
>is quite
>large but the trailing edge is just as robust as the
>rest of the glider
>so handling the 140 Lb. wing isn't a problem.
>With a large elevator at the trailing edge there could
>be an
>assembly/disassembly issue. Would it be separately
>removable
>or fixed to the wing? The elevator on the Genesis
>weighs less than
>10 Lbs. and is short enough that you can stick it under
>your arm or
>carry it off with one hand. The Genesis has a cockpit
>large enough
>for a 6'10' 255 Lb. pilot to move around in. I think
>just the size of
>it is as great a 'hindrance' to performance as any
>other trade off.
>
>
>
>

[Martin Gregorie[_1_]]

Nyal Williams wrote:
> 6'10'? 255lbs? What are the load limits for this
> glider?
>
The Sailplane Directory gives 298 kg (!) and shows no provision for
water ballast, so presumably that's all pilot.

This seems a bit unlikely; can it be right?


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

[Steve Davis]

At 06:06 11 July 2007, Nyal Williams wrote:
>6'10'? 255lbs? What are the load limits for this
>glider?
Genesis Flight Manual, Section 2.9
The Genesis 2 glider is a single seat aircraft. Unless
lead trim weights are used the cockpit load is limited
to the following range: 154 lbs. to 242 lbs. (70 kg
to 110 kg)

While also staying within the other parameters, Max.
TO
weight without water ballast: 807 lbs., Max. weight
of all
non-lifting parts: 531 lbs., you could get up to 255
- 260.

Still, the Genesis 2 wing, assuming a 310 lb. load
(260 pilot and 50 gear), was tested to 19g. before
breaking.
There was discussion that perhaps the test fixture
failed,
concentrating the force and causing the wing to snap.
I can
imagine that, given the unique shape of the Genesis
wing and
the fact that most glider wings will fail at 10 to
12g, rolling or
twisting forces could have occurred causing the spar
to break
at 'only' 19g. Perhaps that explains why the Genesis
2 in the
video had no damage to the wing.

[Steve Davis]

The Genesis 2 can hold 26 gal. of water in each wing.
Max. TO weight with water ballast is 1157 lbs. (525kg)

At 14:06 11 July 2007, Martin Gregorie wrote:
>Nyal Williams wrote:
>> 6'10'? 255lbs? What are the load limits for this
>> glider?
>>
>The Sailplane Directory gives 298 kg (!) and shows
>no provision for
>water ballast, so presumably that's all pilot.
>
>This seems a bit unlikely; can it be right?
>
>
>--
>martin@ | Martin Gregorie
>gregorie. | Essex, UK
>org |
>