Which bird thermals the best?

[Scott Alexander[_2_]]

So in a recent conversation with a greatly experienced soaring pilot,
I was told that Buzzard's have terrible thermaling skills. I tend to
agree with this as it sure seems Buzzards don't get into the core and
stay there. The lesson learned was don't let Turkey Buzzard show you
where the core is, just let them lead you to the thermal.

I thought it would be interesting to ask you good people if anyone has
any knowledge on these issues. Does anyone know which broad winged
birds have better or worse centering techniques that you can use to
your advantage?

SA

[Martin Gregorie[_5_]]

On Mon, 15 Nov 2010 03:59:01 -0800, Scott Alexander wrote:

> I thought it would be interesting to ask you good people if anyone has
> any knowledge on these issues. Does anyone know which broad winged
> birds have better or worse centering techniques that you can use to your
> advantage?
>
About the best I've watched are kites - both the Indian Brown Kites and
the Red Kite that are now spreading across the UK.

You can tell thermal strength by watching them: the stronger the thermal
the more dihedral they use. When its weak their wings are flat and when
its really weak or they think they might undershoot the branch they're
aiming for they have slight anhedral and all the tip feathers are spread
and turned up. They never flap unless they absolutely have to.

The other top birds IMO are storks. I was flying models at a major
contest in Portugal near Beja where the field was dotted by small groups
of them. They were wary and would take off if you got within 50m, but I
never saw them flap longer than it took them to get up 30-40 feet and
they always seemed to slot into something and thermal away. It was a hot,
dry, thermally place, but even so their ability to find a thermal when
scared off at a time that wasn't of their choosing was amazing.


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

[John Smith]

Martin Gregorie wrote:
> About the best I've watched are kites - both the Indian Brown Kites and
> the Red Kite that are now spreading across the UK.

I can't judge it, but I've heard that if there are Swifts, they are
pretty reliably in the core of the thermal (because their food is there).

> The other top birds IMO are storks. I was flying models at a major

Not surprizingly, Otto Lilienthal spent a lot of time watching storks.

[Andy[_1_]]

On Nov 15, 4:59*am, Scott Alexander >
wrote:
> So in a recent conversation with a greatly experienced soaring pilot,
> I was told that Buzzard's have terrible thermaling skills. I tend to
> agree with this as it sure seems Buzzards don't get into the core and
> stay there. The lesson learned was don't let Turkey Buzzard show you
> where the core is, just let them lead you to the thermal.
>
> I thought it would be interesting to ask you good people if anyone has
> any knowledge on these issues. *Does anyone know which broad winged
> birds have better or worse centering techniques that you can use to
> your advantage?
>
> SA

In Arizona red tail hawks are the one of the best thermallers and
turkey vultures among the worst. It may be that the turkey vultures
are only interested in getting high enough to spot their next meal but
the red tails seem to soar for fun. They have no fear of flying with
gliders and it's always a pleasure to share a thermal with one or more
of them.

The red tails usually have the thermal well centered but I have on
occasion had one come over to me when I had the better core.

Andy

[Kevin Neave[_2_]]

Penguins!

Buzzards etc have a much lower wing loading than we do so they'll climb
in small, weak thermals.

With their high wingloading then penguins can't afford to stop for
anything but the best.

Rarely seen soaring, but that's 'cos their inter-thermal speeds are much
higher (Wing loading again), and there's not many other pilots flying in
Antarctica to see them.

KN

[Graemec]

On Nov 15, 10:59*pm, Scott Alexander >
wrote:
> So in a recent conversation with a greatly experienced soaring pilot,
> I was told that Buzzard's have terrible thermaling skills. I tend to
> agree with this as it sure seems Buzzards don't get into the core and
> stay there. The lesson learned was don't let Turkey Buzzard show you
> where the core is, just let them lead you to the thermal.
>
> I thought it would be interesting to ask you good people if anyone has
> any knowledge on these issues. *Does anyone know which broad winged
> birds have better or worse centering techniques that you can use to
> your advantage?
>
> SA

Wedge-tailed eagles are superb. They aggressively push you out if
they find you stopping them centreing accurately. Best of all, they
do it in the blue at all altitudes. They are an unerring guide - just
don't make them feel challenged!

Pelicans are rarer in soaring country but I've seen them up to 6-7,000
feet. They are another species that won't flap unless facing
disaster. They slope soar regularly on the steep harbour shore near
me. Their habit is to move along the slope until they find where the
slope triggers a thermal and then circle away. Given their size (the
747 of soaring birds) they're a lot easier to see than hawks. Unlike
eagles, which just seem to instinctively keep in the best air,
pelicans seem to centre like us by rolling level for a short time and
then rolling back in to a new centre. Beautiful to watch.

GC

[Wayne Paul]

"Kevin Neave" > wrote in message ...
> Penguins!
>
> Buzzards etc have a much lower wing loading than we do so they'll climb
> in small, weak thermals.
>
> With their high wingloading then penguins can't afford to stop for
> anything but the best.
>
> Rarely seen soaring, but that's 'cos their inter-thermal speeds are much
> higher (Wing loading again), and there's not many other pilots flying in
> Antarctica to see them.
>
> KN
>

I think the Golden Eagle should be added to the mix of great thermaling birds. Though not as common as Buteos we often fly with them over the mountains of Idaho.

One should not over look the beauty of a flock of thermaling pelicans with their white bodies and wings with black tips.

Wayne
http://www.soaridaho.com/

[Frank Whiteley]

On Nov 15, 4:59*am, Scott Alexander >
wrote:
> So in a recent conversation with a greatly experienced soaring pilot,
> I was told that Buzzard's have terrible thermaling skills. I tend to
> agree with this as it sure seems Buzzards don't get into the core and
> stay there. The lesson learned was don't let Turkey Buzzard show you
> where the core is, just let them lead you to the thermal.
>
> I thought it would be interesting to ask you good people if anyone has
> any knowledge on these issues. *Does anyone know which broad winged
> birds have better or worse centering techniques that you can use to
> your advantage?
>
> SA

White Storks. Although they can only fly about 30 miles on the flap,
they migrate 6000 miles on thermals. Due to the short flap range,
those that choose there wrong path over the Sea of Marmara drown
there. I've seen an estimated 1,500 in a thermal in Turkey.
Impressive glide also.

Frank Whiteley

[Mike the Strike]

Turkey Vultures are excellent soaring birds, but have a very low wing
loading and use microlift near the ground, which is often patchy and
disorganized. They typically don't soar very high because they eat
carrion, which they locate by smell (Just Google it if it sounds too
unlikely). They are generally not much use to glider pilots for these
reasons.

Vultures that locate prey visually soar higher and appear to thermal
better. These include Africa's Cape Vulture and the American Black
Vulture, both of which I've found like to join gliders in thermals.
Most eagles and largish hawks soar very well, as do storks and
herons. Their L/D is actually worse than most modern sailplanes, but
their advantage lies in slower flying speeds that translates into
tighter turning circles and having a very sensitive vario.

Mike

[Bob]

On Nov 15, 4:59*am, Scott Alexander >
wrote:
> So in a recent conversation with a greatly experienced soaring pilot,
> I was told that Buzzard's have terrible thermaling skills. I tend to
> agree with this as it sure seems Buzzards don't get into the core and
> stay there. The lesson learned was don't let Turkey Buzzard show you
> where the core is, just let them lead you to the thermal.
>
> I thought it would be interesting to ask you good people if anyone has
> any knowledge on these issues. *Does anyone know which broad winged
> birds have better or worse centering techniques that you can use to
> your advantage?
>
> SA

I've been writing some short articles on birds and soaring. I'll
attach some exerpts from one here.

In Arizona and Coloorado the big wing birds I work with most are Red
Tail Hawks. But, when looking for the best cores the little Swifts
are THE best indicators... but you have to look closely to notice
them.

Swifts are a family (Apodidae) of small, highly aerial birds, flying
almost constantly except when at the nest or roosting at night. As
using rising air helps conserve their energy, these little guys are
real pros at working thermals, and they tend to find the best thermals
wherever they fly. They also have impeccable eyesight (about 10X
human eyesight), allowing them to see small insects in the air.
Amongst the fastest flyers in the animal kingdom, the common swift
(Apus apus) can cruise at 12 to 30 mph and is capable of 130 mph for
short bursts. Swifts not only can fly fast, they are incredibly
aerobatic, often changing directions almost instantly, which helps in
their quest for dinner in thermals.

Back when I was flying hang gliders cross-country, we saw them often
(commonly above 16,000’), and when we did, we knew we were in the best
part of one of the best thermals of the day. Sitting under the hang
glider, fully exposed to the elements, I had a “front-row seat” to
watch swifts dart around me in good thermals. It was not unusual to
see them zip in between my wings and flying wires, often within a foot
or so of me. Incredible flying accuracy. Little wonder one of the
première aerobatic gliders is aptly named the SWIFT!

Powerful thermals vacuum insects from the surface and propel them
skyward, and swifts have an uncanny knack for spotting these swirling
aerial food bazaars, utilizing them for high altitude feasting. In
the spring of 2009 I was flying with a friend, Ted Grussing, in his
Lambada motorglider on a good soaring day, and we worked some pretty
nice thermals going to and from the Grand Canyon. It was one of those
days when about ¾ of the clouds were duds, as far as good thermals
were concerned. On the way back, we glided over to the best looking
cloud of the day, and rode the elevator up. Seeing a swift dart by as
I was making the 3rd 360, I immediately turned to core what he was
in. Bingo! Our 12 kt average leaped to 17 kts in the tight core.
Yahoo! Crank & bank! The good looking cloud had attracted us, but
the swifts helped me find the best part of the core. The last we saw
of them was when we were pulling out at 17,500’. Those little guys
obviously aren’t concerned about class A airspace….

Bob T.
19

[John Smith]

Frank Whiteley wrote:
> White Storks. Although they can only fly about 30 miles on the flap,
....
> Impressive glide also.

But as research has shown, they have no clue of the McCready theory:
http://infonet.vogelwarte.ch/upload/00544921.pdf

[Brad[_2_]]

On Nov 15, 3:59*am, Scott Alexander >
wrote:
> So in a recent conversation with a greatly experienced soaring pilot,
> I was told that Buzzard's have terrible thermaling skills. I tend to
> agree with this as it sure seems Buzzards don't get into the core and
> stay there. The lesson learned was don't let Turkey Buzzard show you
> where the core is, just let them lead you to the thermal.
>
> I thought it would be interesting to ask you good people if anyone has
> any knowledge on these issues. *Does anyone know which broad winged
> birds have better or worse centering techniques that you can use to
> your advantage?
>
> SA

Red Tailed Hawks and their brethren seem to be the best at
thermalling, they have helped me numerous times.

Turkey Vultures are great for following, IF they are going up, once
they hit the thermal all hell breaks loose and they thermal in very
unruly groups. They seem to be really good at finding micro-lift
threads.

Swallows and Swifts don't seem to really "thermal", I suspect they
just get sucked straight up while chasing bugs............but I've
seen these guys many times at cloudbase bombing around like fighter
planes.

Soaring would be a lonely place without our raptor friends!

Brad

[Herbert kilian]

On Nov 15, 5:59*am, Scott Alexander >
wrote:
> So in a recent conversation with a greatly experienced soaring pilot,
> I was told that Buzzard's have terrible thermaling skills. I tend to
> agree with this as it sure seems Buzzards don't get into the core and
> stay there. The lesson learned was don't let Turkey Buzzard show you
> where the core is, just let them lead you to the thermal.
>
> I thought it would be interesting to ask you good people if anyone has
> any knowledge on these issues. *Does anyone know which broad winged
> birds have better or worse centering techniques that you can use to
> your advantage?
>
> SA

An excellent soaring bird has not been mentioned: the Sandhill Crane.
Although I have never soared with them, I watch hundreds of them per
flock migrating from and to N. Wisconsin and Canada over our Western
Chicago suburb each fall and spring. They wait for the right wind
direction and instability (which there is not much of especially in
fall) and climb/run as we do without batting a wing. They go into
formation while running but the flock is without structure while in a
thermal. They are magnificent large birds and their cries are very
distinct.

They are the first reliable sign in early to mid March that the Winter
is on the way out and their sights and sounds are very much welcomed.
Herb, J7

[Bob Whelan[_3_]]

On 11/15/2010 8:50 AM, Mike the Strike wrote:
> Turkey Vultures...<Snip>...typically don't soar very high because they eat
> carrion,

Which reminds me...why don't we see Turkey Vultures on commercial airliners
much anymore?
..
..
..
..
..
..
..
..
..
..
<Wait for it...>
..
..
..
..
..
..
..
..
..
Too many restrictions on carrion luggage!!!



Please...no need to thank me.

[Frank Whiteley]

On Nov 15, 9:08*am, John Smith > wrote:
> Frank Whiteley wrote:
> > White Storks. *Although they can only fly about 30 miles on the flap,
> ...
> > Impressive glide also.
>
> But as research has shown, they have no clue of the McCready theory:http://infonet.vogelwarte.ch/upload/00544921.pdf

Neat paper.

[Grider Pirate]

On Nov 15, 9:24*am, Bob Whelan > wrote:
> On 11/15/2010 8:50 AM, Mike the Strike wrote:
>
> > Turkey Vultures...<Snip>...typically don't soar very high because they eat
> > carrion,
>
> Which reminds me...why don't we see Turkey Vultures on commercial airliners
> much anymore?
> .
> .
> .
> .
> .
> .
> .
> .
> .
> .
> <Wait for it...>
> .
> .
> .
> .
> .
> .
> .
> .
> .
> Too many restrictions on carrion luggage!!!
>
> Please...no need to thank me.

Oh, MY, DOG! Yer' KILLIN' me!
Good one Bob

[Bill Bullimore[_2_]]

One obvious master of the master class has not yet been
mentioned: the Frigate Bird.

I have seen them soaring over water on calm days, seen them
wings tucked forward and gliding well into a 35 knt wind. They are
on the wing all day, mate on the wing, not only are they the best
soaring birds by a LONG way, they have by far the best l/d. Just
look at their wing form - they are all about aspect ratio and going
places.

They not only out-soar all other forms of soaring birds, but steal
their food from them as well! (hence the name, also called Man o'
War birds).

Incidentally, having glid with pelligoons many times in the
Caribbean, I can vouch that pelicans and hang gliders have about
the same l/d and sink rate. However, they are much better at
diving into water, although I did try that once, but it is a hard way
to make a living.

anyway, Frigate birds rule!

bwBB

[Berry[_2_]]

In article
>,
Scott Alexander > wrote:

> So in a recent conversation with a greatly experienced soaring pilot,
> I was told that Buzzard's have terrible thermaling skills. I tend to
> agree with this as it sure seems Buzzards don't get into the core and
> stay there. The lesson learned was don't let Turkey Buzzard show you
> where the core is, just let them lead you to the thermal.
>
> I thought it would be interesting to ask you good people if anyone has
> any knowledge on these issues. Does anyone know which broad winged
> birds have better or worse centering techniques that you can use to
> your advantage?
>
> SA

Others have mentioned swifts. Here in the eastern U.S. they seem to me
to be the best tell-tale of a superior thermal.

One bird that has not been mentioned, but is a great indicator of a good
thermal, is the Anhinga. They are also known as the snake bird or water
turkey. In flight, they look like an arrow with high aspect ratio wings
attached. They are a water bird so are usually around the low, wet
places we sailplane pilots dread. I have only found them thermalling in
good lift. Look for them the next time a sadistic CD puts your course
line right down a river valley or across a swamp or lake.

[noel.wade]

On Nov 15, 8:48*am, Herbert kilian > wrote:

> An excellent soaring bird has not been mentioned: the Sandhill Crane.

Very true, Herbert!

In Central/Eastern Washington State there's a big Sandhill Crane
migration every spring... We can hear the huge flocks on the ground
as they pass over our gliderport at several thousand feet - loud
conversationalists, they are!

I've never shared a thermal with one, but I've flown near them and
noticed they have an uncanny knack for finding shear-lines and
streets. Someday I'll figure out how to take advantage of those
myself... :-P

--Noel

[sisu1a]

> One obvious master of the master class has not yet been
> mentioned: *the Frigate Bird.

> They not only out-soar all other forms of soaring birds, but steal
> their food from them as well! (hence the name, also called Man o'
> War birds).

Well, another obvious bird not mentioned is the Albatross, which has
the highest aspect of all birds (higher aspect then Frigatebirds,
which hold the title for the lowest span loading, no doubt
contributing to their ninja-like agility...). Sorry Frigates, but the
Alby is the true unequivocal champion of *soaring, although in spirit
of the OP's question, the Frigatebird may out perform it in a
thermal ... Albatross circumnavigate the globe though, no doubt
expertly working thermals the rare occasions they're available, but
mostly use orthographic and different of modes of dynamic soaring (as
do Frigatebirds) for their constant open water X/C trips, living life
'on the wing' stopping only to raise chicks from time to time.

Frigatebirds are indeed amazing, and are definitely beautiful birds to
share the air with as well as to watch from the ground. So far I have
only soared with Frigatebirds, (Hawaii), but very much look forward to
the day I share the air with an Alby... (not the bronze statue,
although that'd be swell too ;)

They're both Peligoonformes though ;)

-Paul

[Mike the Strike]

On Nov 15, 7:29*pm, sisu1a > wrote:
> > One obvious master of the master class has not yet been
> > mentioned: *the Frigate Bird.
> > They not only out-soar all other forms of soaring birds, but steal
> > their food from them as well! (hence the name, also called Man o'
> > War birds).
>
> Well, another obvious bird not mentioned is the Albatross, which has
> the highest aspect of all birds (higher aspect then Frigatebirds,
> which hold the title for the lowest span loading, no doubt
> contributing to their ninja-like agility...). Sorry Frigates, but the
> Alby is the true unequivocal champion of *soaring, although in spirit
> of the OP's question, the Frigatebird may out perform it in a
> thermal ... Albatross circumnavigate the globe though, no doubt
> expertly working thermals the rare occasions they're available, but
> mostly use orthographic and different of modes of dynamic soaring (as
> do Frigatebirds) for their constant open water X/C trips, living life
> 'on the wing' stopping only to raise chicks from time to time.
>
> Frigatebirds are indeed amazing, and are definitely beautiful birds to
> share the air with as well as to watch from the ground. So far I have
> only soared with Frigatebirds, (Hawaii), but very much look forward to
> the day I share the air with an Alby... (not the bronze statue,
> although that'd be swell too ;)
>
> They're both Peligoonformes though ;)
>
> -Paul

I've not seen too many frigate birds or albatrosses in Arizona. Maybe
they are ill equipped to survive on a diet of lizards and pack rats!

Mike

[John Smith]

sisu1a wrote:
> Well, another obvious bird not mentioned is the Albatross, which has

The original question was about birds to be useful markers for soaring.
I'm not sure I would want to try and follow an albatross and cross the
oceans with dynamic soaring a few feet above the water...

[Wiktor Moskwa]

On 15 Lis, 12:59, Scott Alexander >
wrote:
>
> I thought it would be interesting to ask you good people if anyone has
> any knowledge on these issues. *Does anyone know which broad winged
> birds have better or worse centering techniques that you can use to
> your advantage?
>

In Poland Hawks are very good thermal indicators and they're quite
common.
Most of the time I find better lift when I move closer to them.

From what I've heard Eagles are even better but they're very rare here
and
I haven't had a pleasure of meeting one.

I would avoid White Storks, especially on weak days - they're great
soarers
but they're low wing loading let's them use thermals that would just
reduce
glider's descent rate a bit.

--
Wiktor

[JC]

A few years ago I was sharing a thermal with three storks at 1800 m
and it seemed that one of them was very young and had not mastered its
thermaling technique quite yet. It would make sudden corrections and
flap a few times while the other two calmly circled and waited for it
to catch up. When they got together they took off in tight formation.
I was headed in about the same direction so I was able to watch them
for several miles and I was amazed by their glide speed which appeared
to be close to 80 km/h. Truly incredible birds.. I don´t know if they
soar for fun but it looked like they were having a great time.

Regards,

Juan Carlos

[Martin Gregorie[_5_]]

On Tue, 16 Nov 2010 03:26:01 -0800, Wiktor Moskwa wrote:

>
> I would avoid White Storks, especially on weak days - they're great
> soarers but they're low wing loading let's them use thermals
> that would just reduce glider's descent rate a bit.
>
According to Henk Tennekes ("The simple science of flight") a bird can't
make a living unless its min.sink speed is 1 m/s or less. I'd think that
land birds are unlikely to be much better than that sinply because the
amount of wing they'd need would make life awkward in trees, etc.

Our gliders can certainly outperform some soaring birds. Some years ago
on an almost flat calm evening I was sitting in a very weak thermal,
flying an SZD 51-1 Junior slowly in fairly wide circles and climbing at
half a knot or less, but hey, it was a nice evening and the drift wasn't
taking me anywhere, so I was just enjoying my last flight of the day.
After a while I was joined by a pair of black-backed gulls. They flew
several turns without gaining on me and then left, coming back 5 minutes
later and somewhat lower. This time they flew one turn and exited, not to
be seen again. I could almost hear one of them saying as they flew off
"See, I told you that thermal was too weak last time".


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

[Dan[_6_]]

On Nov 16, 4:03*am, JC > wrote:
> A few years ago I was sharing a thermal with three storks at 1800 m
> and it seemed that one of them was very young and had not mastered its
> thermaling technique quite yet. It would make sudden corrections and
> flap a few times while the other two calmly circled and waited for it
> to catch up. When they got together they took off in tight formation.
> I was headed in about the same direction so I was able to watch them
> for several miles and I was amazed by their glide speed which appeared
> to be close to 80 km/h. Truly incredible birds.. I don´t know if they
> soar for fun but it looked like they were having a great time.
>
> Regards,
>
> Juan Carlos

a few years ago I shared a thermal with a whole flock of Geese. They
were in a typical V formation then they hit the thermal, turned into
the wind and just hung there, they did break formation a little. I
circled around them as we all climbed together. It appeared they just
sort of took a rest break in the air, hovering in one spot. After a
while they turned back North and re-formed the V formation but seveal
hundred feet higher. It was really cool to watch.

Dan
WO

[Justin Craig[_2_]]

I hear Gill Spreakley is pretty good!

[Tony[_5_]]

on my last flight in the Cherokee there were a bunch of seagulls
flying around. they thermal but they suck at it. the were never in
the core and are a pain to gaggle with as they are just a huge blob of
birds. I was at some times surrounded above and below and on all
sides by hundreds of birds. one thing they are good at is getting out
of the way

[HZ]

On Nov 17, 6:39*pm, Tony > wrote:
> on my last flight in the Cherokee there were a bunch of seagulls
> flying around. *they thermal but they suck at it. *the were never in
> the core and are a pain to gaggle with as they are just a huge blob of
> birds. *I was at some times surrounded above and below and on all
> sides by hundreds of birds. *one thing they are good at is getting out
> of the way

When you see thermaling pelican, you can start very slow preparation
for take-off ;)
Valid at Australia http://picasaweb.google.com/diana2.szd56.2.vh.vhz/GlidingPictures#5399607300185961682

Greetings, Hana

[BruceGreeff]

Birds I have thermalled with -

Cape Griffon (White Backed Vultures) thermal very well, but you have to
be careful there is a "vulture restaurant" near the Drakensberg Club
outside Underberg. (Natal Province - South Africa) So sometimes you join
them in a thermal, only to discover they have sought out the descending
air so they can get on the ground for grub. They are gregarious and join
the gliders quite happily. Occasionally you get one clown who thermals
the wrong way and causes chaos.

Bearded vulture - this is a huge bird, which I have only had the
priviledge of flying with once as they don't like gliders and get
aggressive - Based on a sample of one Two up in a K13, and trying to
stay up in the only thermal in the sky trickling off a stony conical
hill. Desperately clinging to about .5kt we got thrashed in the Grob 103
Twin Astir - The Cape Griffon with us were also left in his dust. One
assumes that the massive wings help. I was interested to see the camber
on the wings changing as the bird optimised the smallest variations in
lift. They eat the marrow in bones, so meal times consist of descend to
a carcass, lift off with a heavy ungainly load and climb high - then
drop the bone onto rocks to break it - descend to eat - fly back to
carcase. Repeat. Clearly those that can thermal well get to eat best.

Tawny Eagle on the Platberg ridge also out climbed me - this time in a
K13 - maybe it is the way I fly. We met doing the 180 turn at the end of
one beat. The Eagle turned well inside us and was clearly able to stay
in a very tight , very strong core of lift rising up from a gulley.

Gymnogene - flew a couple of turns with me in a Bergfalke II-55. It was
late afternoon, and I think the motivation was curiosity on the way to
it's roost for the night. I got carefully inspected and then left - at
about the same height. Sample of one does not say much, but despite the
wing aspect ration he was not climbing well. Also - This is the only
solo bird I have had join me in a thermal and turn opposite.

Yellow Billed thermal very well. They have often helped me over the
Vredefort dome - generally marking good lift.Problem is they are so
agile they can use lift which even the Cirrus can't turn in...

European swifts are often to be seen right in the core of strong
thermals at high altitude. The seem to be able to combine hawking
insects and thermalling with relatively little flapping in between the
aerial gymnastics. They really get into the core of the thermal.

Never flown with them but the Bateleur Eagles seem to thermal very well
too.



On 2010/11/15 1:59 PM, Scott Alexander wrote:
> So in a recent conversation with a greatly experienced soaring pilot,
> I was told that Buzzard's have terrible thermaling skills. I tend to
> agree with this as it sure seems Buzzards don't get into the core and
> stay there. The lesson learned was don't let Turkey Buzzard show you
> where the core is, just let them lead you to the thermal.
>
> I thought it would be interesting to ask you good people if anyone has
> any knowledge on these issues. Does anyone know which broad winged
> birds have better or worse centering techniques that you can use to
> your advantage?
>
> SA

--
Bruce Greeff
T59D #1771 & Std Cirrus #57

[mgh3485]

I came across another contender this week for best thermalling bird,
although not really a bird... more an extinct flying reptile.
Apparently the Quetzalcoatlus (largest of the pterosaurs) might have
been quite the efficient soarer, with a 10m+ wingspan. Here's the
article: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0013982.
Figure 2 is the most relevant for this discussion, with a nice two-by-
two diagram mapping bird and pterosaur species based on their aspect
ratios and wing loadings.

The theorized launch method was potentially quite unique as well
(quadrapedal launch), although not likely to replace the aerotow or
winch launch. There's a video recreation with this story:
http://news.sciencemag.org/sciencenow/2010/11/large-size-didnt-keep-pterosaurs.html?ref=hp

Coincidentally, there even happens to be a photographic depiction of
an attempt to thermal with Quetzalcoatlus (http://tv.sky.com/3d-
attenborough-doc-to-debut-this-xmas). I think by the look on Sir
David Attenborough's face he must have been wishing the giant reptile
were FLARM equipped.

[ContestID67[_2_]]

I have to vote for the Sandhill Cranes also. If for no other reason
that their flocks are so large, and they seem to thermal in the same
direction, that they can form the outline of the thermal. Very cool
to see and a pretty bird to boot.

Turkey vultures I have seen ridge soaring at Devil's Lake in
Wisconsin. But not a good looking bird.

Then again being land locked we don't see many frigate birds,
albatrosses, etc, etc,

- John DeRosa