I think I Saw One, Once

Hey, I read your topic concerning aircraft stopping in midair and
would like to ask another question that I hope isn't considered
stupid.

Here goes, "why" is it so hard to believe?

I once went to an air show in New York when I was much younger and
there was an airplane that did stunts in the air.

It was a propeller plane which I don't know what kind and it did a
whole string of fancy flying that had the crowd in awe.

One of the flyer"s moves put the aircraft in a loop than a climb. We
watched for the next trick but then the plane's motor cut out and he
just stopped in the air. We all looked up and it just sat there for a
minute, not moving.

Is this considered really stopped or was the altitude making it an
optical illusion?

Was the flyer still slightly moving?

Anyhow, he dropped down, restarted his engine, and then did more
tricks.

I'll never forget that sight though. I was so scared at first that an
accident might happen but the sight of the plane in suspension was
wonderful.

Oh yeah, mister smarty-pants at my work said that the Reds can stop in
the air. I had to write down the aircraft he listed and these
comments, "one of the very first Su-27 aircraft discovered 0 IAS on a
test flight after developing an inflight control problem. Nosing up
into high AOA the aircraft stood on its tail and stopped in midair for
an alarming 18 seconds at 8,000m before the aircraft dropped back down
and rolled free". He said the flight occurance was reported and
documented a long time ago.

Can anyone disprove this guy? What is a Su-27, a prototype or what?


James Dandy

"James Dandy" wrote in message
m...
One of the flyer"s moves put the aircraft in a loop than a climb. We
watched for the next trick but then the plane's motor cut out and he
just stopped in the air. We all looked up and it just sat there for a
minute, not moving.

Is this considered really stopped or was the altitude making it an
optical illusion?

Either it was still moving, or the prop was still turning at a rate high
enough for it to prop-hang, being held up by thrust alone (i.e. zero
aerodynamic lift from the airframe.) Gravity doesn't allow for any other
alternative.

Can anyone disprove this guy? What is a Su-27, a prototype or what?

Su-27 is the Russian "Swan", or NATO designation Flanker. It can perform
Pukachev's(sp?) Cobra manouever where the aircraft stalls at 90 degrees.
Again, gravity will dictate that it then slides backwards, at which point
the pilot points the nose down and increases power to regain controlled
flight. It cannot hang stationary in the air if the engines are out. There
was a prototype Su 27 variant that had thrust vectoring, which enabled it to
hover in stable conditions for a short time. It's not in itself a useful
capability, i.e. it cannot loiter, take of or land in that configuration,
and it burns a consireable amount of fuel doing it, while completely
ordnance-free.

Si

"James Dandy" wrote in message
m...
Hey, I read your topic concerning aircraft stopping in midair and
would like to ask another question that I hope isn't considered
stupid.

Here goes, "why" is it so hard to believe?

I once went to an air show in New York when I was much younger and
there was an airplane that did stunts in the air.

It was a propeller plane which I don't know what kind and it did a
whole string of fancy flying that had the crowd in awe.

One of the flyer"s moves put the aircraft in a loop than a climb. We
watched for the next trick but then the plane's motor cut out and he
just stopped in the air. We all looked up and it just sat there for a
minute, not moving.

Is this considered really stopped or was the altitude making it an
optical illusion?


Its possible for an aircraft to have zero ground speed if its stall speed
is lower than wind speed

I recall seeing a Fiesler Storch apparently hovering at an air show but
what was happening was there was a stiff breeze blowing so its
airspeed was above the region where a stall would occur but it was
basically standing still with regard to the ground.

Keith

Back in 1988 at an airshow at the Allegheny County Airport, Pittsburgh, Pa.,
I saw demonstration flight with a Piper Cup in a stiff breeze in which he
did hover over a particular spot for about ten minutes going up and down and
goosing the throttle..


"Keith Willshaw" wrote in message
...

"James Dandy" wrote in message
m...
Hey, I read your topic concerning aircraft stopping in midair and
would like to ask another question that I hope isn't considered
stupid.

Here goes, "why" is it so hard to believe?

I once went to an air show in New York when I was much younger and
there was an airplane that did stunts in the air.

It was a propeller plane which I don't know what kind and it did a
whole string of fancy flying that had the crowd in awe.

One of the flyer"s moves put the aircraft in a loop than a climb. We
watched for the next trick but then the plane's motor cut out and he
just stopped in the air. We all looked up and it just sat there for a
minute, not moving.

Is this considered really stopped or was the altitude making it an
optical illusion?


Its possible for an aircraft to have zero ground speed if its stall speed
is lower than wind speed

I recall seeing a Fiesler Storch apparently hovering at an air show but
what was happening was there was a stiff breeze blowing so its
airspeed was above the region where a stall would occur but it was
basically standing still with regard to the ground.

Keith

U¿ytkownik "Keith Willshaw" napisa³ w
wiadomo¶ci ...

"James Dandy" wrote in message
m...

[snip...]

Its possible for an aircraft to have zero ground speed if its stall speed
is lower than wind speed

Not only. THEORETICALLY every modern fighter could do this trick. With
thrust-to-weight ratio more than 1, which is normal for modern fighters,
they could (repeat: THEORETICALLY!) stand vertically on the fire. This would
be flying circus trick rather than any usable manoeuver. And YES, there were
experimental VTOL aircraft (the 'Tail Sitters': Convair XFY-1 Pogo, Locheed
XFV-1, Ryan X-13 Vertijet) but the designs were abandoned as 'dangerous and
unpractical'. Starting from the page
http://www.airandspacemagazine.com/a...e/QT/menu.html you can see
some QuickTime clips with these aircraft during start/landing/hovering.

I recall seeing a Fiesler Storch apparently hovering at an air show but
what was happening was there was a stiff breeze blowing so its
airspeed was above the region where a stall would occur but it was
basically standing still with regard to the ground.

Not only. I recall a photo made in multiple-exposure mode in which Helio
550A Stallion (AU-24 for military pilots) took-off with head wind. After few
minutes aircraft was some 500-600 feet ABOVE starting point nad had NEGATIVE
ground speed. I saw this picture in Polish air-enthusiast's weekly
'Skrzydlata Polska' in late 60s or early 70s.

I heared also a story about An-2 from roughly the same time. This could be
urban legend, but is interesting.
It happened at Warsaw Okecie airfield. The place is important, so I tell you
that this airfield has 2 active runways (15/33 and 11/29 intersecting in the
middle). The NW edge of the airfield (between runways 29 and 33) is shared
by aircraft factory (PZL Okecie) and Aviation Institute (ILot). Third runway
(and oldest one) runs east-west just off the PZL/ILot fence; it is not used
for years and was degraded to taxi-way role. Test pilots of both firms
rarely used regular runways; they used to take off from the oldest runway
or from the grass across the airfield.
One time an PZL test pilot was flying An-2 home from south. He contacted the
tower, received approval and intended to land usual way i.e. on the grass.
He was on final approach when tower ordered him to wait in the air until
scheduled airliner made his landing. An-2 was first there and should have
priority (one engine versus 2- or 4-engined airliner). There was strong
headwind so the guy in An-2 flew to the runways' crossing, raised aircraft's
nose, slats and flaps on - practically hovering 50 ft above ground, and
reported to the tower 'OK, I'm waiting'. The tower was flabbergasted.
Fortunatelly the captain of the other aircraft acted quickly and went
around. The story don't tell the fate of An-2 pilot.


Keith

BTW the name of the airplane you saw is FIESELER Fi-156 Storch. Art Kramr
usually spells that name Feisler. ;-(

Regards
JasiekS
Warsaw, Poland