Hi Gang
Without belaboring it I think it has been said enough times that
currently there is no single fool proof way to guaranty avoiding mid
airs. Having an operating transponder, without argument, will diminish
your chance of a mid air since both ATC and aircraft with TCAS or PCAS
will see you. You may not see them and that is why in my world,
without argument, you should also have, at the minimum, a PCAS so that
you will see another aircraft with an operating transponder. A Zaon
PCAS can be had for only $500 - a trivial amount when it comes to
safety. I don't know why we are still discussing these issues -
transponders and PCAS are mandatory safety devices in my world. I
can't think of a reason why anyone would think otherwise.
Dave

On Jan 22, 11:35*am, wrote:
On Jan 19, 4:24*pm, Martin Gregorie



wrote:
On Mon, 19 Jan 2009 10:06:40 -0800, Darryl Ramm wrote:
I know nothing about UK airspace (besides being stuck in it for far too
much time as a passenger holding over Heathrow), but it sounds like the
existing separation of airliner and jets in UK airspace is a key point
you folks should be arguing.

Yes, agreed. The public will be with us on noise grounds if the commuter
airlines get their way and start flying direct routes through class G
airspace - this is something they can't do at present, but the CAA's
transponder consultation seems designed to let them do it.

And again only one of the transponder aircraft needs to be talking to
ATC/radar facilities or have PCAS or higher. *I don't know PCAS (and
higher-end systems) adoption in low-end GA aircraft in the UK, but in
the USA it seems pretty high (purely an anecdotal impression). I've
asked before but could not get adoption numbers for the USA.

I've not seen figures either, but the GA density is probably lower here..
There are flying schools on either side of our club field and there's no
doubt that our weekend movements vastly outnumber both of theirs.

In the Libelle you might be able to make up a mount for a Zaon MRX under
the opaque areas of the front of the canopy.

There's less space there than you might imagine. The panel is inset no
more than 65mm (2.5"), so an end-on cigarette pack would not fit under in
font of the panel while anything thicker would start to hide the top row
instruments.

It might be canted over parallel to the surface,

It would have to be. If it was in the center it would interfere with the
canopy lock. On the other hand, the antenna is probably not an issue - a
remote one could be mounted above the instrument tray that forms the
front of the panel. My GPS antenna is mounted there and gets an excellent
view of the sky.

I wouldn't want anything much bigger than a MH flowmeter on the cockpit
wall in front of me: lets just say the cockpit is 'snug'.

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

The proponents of transponders in gliders should study a recent
Transportation Safety Board of Canada investigation report into a
tragic mid-air collision between a Cessna 182 and a Cessa near Toronto
in August 2006. Three people died in the collision. The full
investigation report is available on the TSB web site athttp://www.tsb.gc..ca/eng/rapports-reports/aviation/2006/a06o0206/a06o...

The TSB report states: "Both aeroplanes were operating in accordance
with visual flight rules in Class E airspace....Both aeroplanes were
equipped with functioning transponders. C-GCHN was also equipped with
a traffic information service (TIS) system that can provide a display
of nearby aircraft using information provided by ground-based radar;
this service is not available in Canada."

A transponder can reduce the risk of collision with Traffic Collision
Advisory System (TCAS) equipped aircraft, i.e. mostly air transport
category aircraft. Maybe that reduction in risk is worth the cost in
some places.

However, as this accident shows, simply installing a transponder gives
no guarantee against collision with non-TCAS equipped aircraft.

Ian Grant
Ottawa Canada