U.K. near-midairs

I'm aware of one airplane/glider collision in the UK
not with 4 miles of the gliders base. A piston single
cruising at about 140 knots ran into the back of a
std cirrus on a staight glide. If I remeber correctlythe
glider pilot was probably killed by the aircrafts propeller.
I think the airplane pilot survived.

I'm also aware of one in the UK and one in the USA
where, although near the gliders base airports, both
involved transiting powered airplanes - so not 'landing
related'. In both cases the powered airplane removed
the outboard few feet of the gliders wing. Both gliders
landed safely, both airplane pilots were killed.

Some years ago, as part of a discussion with officialdom
about proposed increases in regulated airspace, I did
a calculation that suggested that incidents that one
might expect an airplane pilot to report as a near
miss (which I reckoned was passing within 500 feet
vertically and 300 yards horizontally of another aircraft
and not seeing early enough to take avoiding action)
would occur about 1000 times more often than actual
collisions.

At 20:30 25 November 2004, Mark James Boyd wrote:
Peter Seddon wrote:
'Gliders in the U.K. were involved in 10 near-midairs

The difference between a mid-air and a near-midair
is
certainly an interesting topic. While in contact with
ATC
in busy airspace I've frequently had jittery airline
FOs
call me as threatening traffic over a mile away. I'd
guess if you're an airline guy and you see ANY aircraft,
and it wasn't on your TCAS, you'd just automatically
call it
a near-midair.

In the US, I'm not aware of any ACTUAL midair collisions
between a
glider and non-glider that are more than 4 miles from
an airport.

I know of lots and lots of talk about near-midairs,
and significant
pressure by the airlines to require transponders in
more
ways. Can we blame them? The FIRST mid-air could
result
in hundreds of deaths...

So there hasn't been one yet, and it's very hard to
tell
how close we've REALLY been to having a glider-airplane
midair
that wasn't very near an airport traffic pattern or
approach.
I'm guessing this is trivial, and requiring transponders
in gliders is a solution looking for a problem.

Have there been any actual airplane-glider midairs
in the UK
that weren't takeoff/landing related (within 4 miles
of the airport)?

in the second half of last year, safety investigators
said recently, noting that newer models fly at high
altitudes without transponders and are hard to see,
both visually and on radar....'

http://www.avweb.com/eletter/archive...ull.html#18860
0


e.g.,

Perhaps spam can pilots should look out of the window
more often!!

Another possibility is a radar reflector installed
in the glider.
These things are much cheaper than a transponder, and
would give at least
some info...

I'd love to see if my local boating supply shop has
one that would fit
--

------------+
Mark J. Boyd

There was another collision.

It was over Farnborough airfield between a glider from the Farnborough
gliding club and a light aircraft from Blackbushe.

The Astir pilot baled out and landed safely on the airfield.

The power pilot flew back to Blackbushe with his pupil instead of landing on
the vast airfield underneath him.

W.J. (Bill) Dean (U.K.).
Remove "ic" to reply.


"Chris Rollings"
wrote in message ...

I'm aware of one airplane/glider collision in the UK
not with 4 miles of the gliders base. A piston single
cruising at about 140 knots ran into the back of a
std cirrus on a straight glide. If I remember correctly the
glider pilot was probably killed by the aircrafts propeller.
I think the airplane pilot survived.

I'm also aware of one in the UK and one in the USA
where, although near the gliders base airports, both
involved transiting powered airplanes - so not 'landing
related'. In both cases the powered airplane removed
the outboard few feet of the gliders wing. Both gliders
landed safely, both airplane pilots were killed.

Some years ago, as part of a discussion with officialdom
about proposed increases in regulated airspace, I did
a calculation that suggested that incidents that one
might expect an airplane pilot to report as a near
miss (which I reckoned was passing within 500 feet
vertically and 300 yards horizontally of another aircraft
and not seeing early enough to take avoiding action)
would occur about 1000 times more often than actual
collisions.

"W.J. (Bill) Dean (U.K.)." wrote in message
...
There was another collision.

It was over Farnborough airfield between a glider from the Farnborough
gliding club and a light aircraft from Blackbushe.

The Astir pilot baled out and landed safely on the airfield.

The power pilot flew back to Blackbushe with his pupil instead of landing
on
the vast airfield underneath him.

W.J. (Bill) Dean (U.K.).
Remove "ic" to reply.

Back in the 70's ( before you were at the Long Mynd) there was an incident
which I witnessed where a pair of Hunters crossed the airfield. Approaching
from the West they slightly diverted apart as if they had suddenly seen the
gliders and the southerly one passed underneath the K13 just as it released
the cable. Two seconds earlier it would have hit the cable whilst it was
attached to the glider.

I was interviewed by an RAF investigator (we had reported the incident) who
stated that the Hunters were based in Germany , were on exercise over the UK
and that their maps showed the Long Mynd as an area of intense gliding
activity.

DB

I'm sure I've seen an article about anti-collision
radar available for corporate aircraft. I believe
that they are available, but am unsure how prevalent
they are. There was some comment about this in AOPA(?)
mag a couple of years ago.

At 18:00 26 November 2004, Btiz wrote:
Nyal, corporate radars are WX radars and not designed
to me air-to-air
intercept radars..

you'd be better off stuffing in a transponder for their
TCAS and for ATC to
really see you.

BT

'Nyal Williams' wrote in message
...
At 03:00 26 November 2004, Ralph Jones wrote:


[snip]

Boating stores sell radar reflectors made of cardboard
and covered with aluminum foil. They are in three
parts and can be disassembled. When put together they
make a sphere about 12-14 inches across and they provide
the 3D right triangles that are supposed to reflect
a signal back.

I inquired about their use in gliders (practically
no weight and could go in fuselage behind wing) and
someone told me they would not give a strong enough
signal for aircraft use owing to the speeds involved.
I have no idea about the validity of this statement.
Couldn't hurt to try it.

That is a corner reflector: three flat, mutually perpendicular
surfaces. It has the special geometric property that
a signal striking
it from any direction will reflect from surface to
surface and wind up
going back exactly the way it came. On radar, it looks
much larger
than an irregular-shaped object the same size.

Apollo crews left at least one optical corner reflector
on the moon,
and astronomers can bounce laser light off it to make
precision
orbital measurements.

Signal strength is not the problem: a fiberglass ship
with a one-foot
corner reflector inside it will look bigger than a
metal sailplane.
The bad news: air traffic control radars are 'moving
target' systems,
which means they filter out returns that don't have
any Doppler shift
to indicate a moving object. I don't know what the
minimum detectable
speed is, but if you're under it, they just won't see
you.

rj



What about the radars in corporate aircraft? If they
can pick it up I might consider stuffing one in the
Discus.

Nyal Williams wrote:
I'm sure I've seen an article about anti-collision
radar available for corporate aircraft. I believe
that they are available, but am unsure how prevalent
they are. There was some comment about this in AOPA(?)
mag a couple of years ago.

It's called TCAS (Traffic Alert/Collision Avoidance System). It's not
radar based, it broadcasts an interrogation signal which causes any
nearby transponders to respond. It calculates range and bearing to
transponders that respond, and shows them on a display in the cockpit.
If there appears to be the threat of collision, it sounds an alarm. If
the other aircraft is TCAS equipped, the two units actually negotiate an
avoidance strategy, then advise the pilots how to maneuver away from the
other aircraft.

Marc

Sometimes that is so; what if you install one because
you want to operate in Class A or B airspace [as opposed
to being more visible in uncontrolled airspace]?

Ian




At 07:30 27 November 2004, Marc Ramsey wrote:
Mark James Boyd wrote:
+ $160/every two years,

It's more like $75-100 every two years, as a transponder
in a glider
just needs VFR certification (i.e., no static leak-down
test).

Marc

Ian Cant wrote:
Sometimes that is so; what if you install one because
you want to operate in Class A or B airspace [as opposed
to being more visible in uncontrolled airspace]?

Assuming you are talking about the US, I've never seen any explicit
requirement for IFR transponder certification for entry into Class B
airspace (assuming VFR operation). As for Class A (outside of a wave
window) you would be operating IFR, so I would guess IFR certification
would be a requirement, as well as the sensible thing to do.

Marc

Ian Cant wrote:
Sometimes that is so; what if you install one because
you want to operate in Class A or B airspace [as opposed
to being more visible in uncontrolled airspace]?

A very rare case indeed. I know of few glider pilots who would operate
in such airspace. I think the stats that 80% of glider pilots twirl
around their home field isn't because of lack of transponders or radios...

On the other hand, here in the states, SSA has proposed to the FAA
allowing glider pilots to legally turn transponders on and off in flight,
to conserve battery power.

I think the FAA is unlikely to approve this. If I'm faced with this
situation, I will notice it is inoperative, turn it off, and place the
appropriate sticker on it. Later in the flight, when I have the time to
test it further, I'll turn it on and notice it works, and I will remove
the sticker.

The other perhaps much more important activity is to learn enough about
the IFR approach procedures near high volume airports where you are
about to fly. The US VFR charts have magenta shaded markings which often
extend from busier airports indicating an IFR approach. Also, for $4-$5
one can purchase the IFR approach plates for a region of the US. Any
instrument pilot can show enough about these to add some perspective.

Of course, this is really mostly to avoid high volume approaches to
commuter airports, but I've used it to assure I avoid commuter traffic
near several gliderports.

--

------------+
Mark J. Boyd

After 20,000+ hours of civilian and military flying, given the number
of times that I have not seen an aircraft until he is _no longer_ a
threat, I have decided that there are probably few, if any, days when
we see all of the traffic in our area throughout the flight.

If we all knew how much traffic we miss, we'd work a lot harder to see
and avoid, and to be seen and avoided.


Jack

Jack wrote:
After 20,000+ hours of civilian and military flying, given the number
of times that I have not seen an aircraft until he is _no longer_ a
threat, I have decided that there are probably few, if any, days when
we see all of the traffic in our area throughout the flight.

If we all knew how much traffic we miss, we'd work a lot harder to see
and avoid, and to be seen and avoided.

Given how much traffic I see within 4 miles of an airport vs. how much I see
during random flight paths away from airports, combined with the midair
accident statistics and my own close calls, I have some conclusions.

I'm very attentive (looking outside) at "D" towered airports.
I fly enroute below 3000 AGL at "off" altitudes (2700, 2340, etc),
except when overflying airports.
I avoid overflying navaids (VORs) and airports, often diverting 5+
miles away/around them.
If I notice an airplane, I immediately assume there are more nearby.
I don't fly in glider gaggles or contests as I don't have the avoidance
skills necessary to feel comfortable.
I only fly near the same thermal/ridge with other gliders if it is exactly
one other glider, or I have two people on board (one as lookout).

Those very experienced in gaggles have different standards, but this
has worked for me so far.




--

------------+
Mark J. Boyd