Bob (re email below)
Dreadle has been in my mind for quite a while, simmering (you might
say)
because of apparent FAA and NTSB wishful thinking on the general
subject of runway incursions. I must admit that the terrible futility of
an SQ006 accident precipitated more thought and I readily agree that it
is no more than semi-refined in its present form. David Evans, as the
Managing Editor of Air Safety Week, is of course required to address
these looming issues and in particular must address the apparent
inability of the regulator to reach a bottom line on effective measures.
He sensed their frustration at a recent summit conference on the issue -
and decided to push the Dreadle to the mettle. It's probably not the
last you'll see about it in ASW. Let's hope it doesn't come to further
prominence because of an accident - but that would be an inevitable and
natural culmination, the way things are presently looking. My
organisation (the International Aviation Safety Association -
IASA) does both think-tank work and ARAC committee work in an
endeavour to address whatever issues we see as a threat to the safety of
the travelling public. ASW is one of our major outlets. We like to float
ideas and inspire people on the inside (such as yourself) - into action.
A climb up the air-safety wish-list for incursions doesn't mean
anything more than that insufficient attention is being paid to a
workable solution.
As I said in that ASW article, attempting to reduce the prevalence of
incursions by a public awareness program is a temporary expedient and
much like praying for rain. The educational approach doesn't cater to
the foreign visiting pilot or casual hire runway vehicle operator
either. In your position you would appreciate that a runway controller
is always daily putting his professional career on the line and when the
inevitable big one happens, he/she might well take an undeserved and
unwholesome share of the blame. I think that Dreadle is an idea that
could work and that is relatively low-tech and inexpensive to boot. The
idea of "arming" a runway against incursion appeals to me
mightily. You have identified a possible failing (snow clearance) - as
well as a possible solution with the inductive loop idea.
Pressure-sensitive transducers are very reliable devices however and
they could be partly recessed into a taxiway by grooving (imagine taut
cables semi-circumferentially recessed into the ground at each position,
about two feet apart - for the permanent installations). For temporary
installations (to cover a W.I.P. situation, say) you would need a
throwdown semi-rigid rubber mat, about six inches wide, 3" incline
either side of the central sensor cable (also in A/B pairs, because the
Dreadle concept relies upon A-B/B-A sensing). Think of the temp install
Dreadle mats as similar to the non-trip rubber floor-grommets (covering
cables) that you see everywhere throughout offices - and that have to
withstand the predations of much pedestrian traffic, roller-seats,
vacuum cleaners and meet occupational health and safety standards (photo
attached). These types of grommets or heavy-duty cable-bridges should be
able to withstand a sweeper overrun -
if held taut enough at the taxiway sides. The USN permanent treadles
for rinse-racks tend to be inlet into the ground. I've seen and used
them at U.S. (and Australian, Norwegian etc) Patrol Plane bases all over
the world -
and they usually work reliably. USN and USAF arrester gear is also
trampled at high-speed on runways and sweepers have to cope with their
presence.
However I agree that Dreadle treadles would proliferate and do need
to be sweeper-proof.
I have not raised the proposition with the FAA simply because these
things best gather momentum and respect if they arise within the
professions (ATC or ALPA) - and so I was hoping for someone like
yourself to come along and pick up the ball. IASA does not patent its
safety ideas and they are free to be exploited by whomsoever. All I ask
is that if you do decide to take that ball and run with it, that you
ensure that they stick to the name of Dreadle. Because IASA is a well
known thorn in the side for Tom McSweeney and Jane Garvey it may be
better to play down its origins also. Good ideas are often depreciated
by the circumstances of their gestation, and the identity of their
progenitors. If you do decide to highlight the virtues of Dreadle with
the DOT/FAA/NTSB hierarchy then I would also appreciate being kept
informed about any progress or obstacles (in addition to David Evans).
I hope you do decide to promote the idea. An even better idea is
sometimes the natural by-product of rejection.
http://www.iasa.com.au/dreadle.htm
US/Europe Site
http://www.pprune.org/cgibin/ultimatebb.cgi?ubb=get_topic&f=6&t=001179
regards
IASA Australasia
http://www.iasa.com.au
-----Original Message-----
From: Bob_Johnson@kcmo.org [mailto:Bob_Johnson@kcmo.org]
Sent: Thursday, 19 July 2001 6:06 PM
To: safety@iasa-intl.com
Subject: Air Safety Week 7/17/01 Dreadle Article
I read your article regarding the above with great interest. While
attending the 2000 FAA Central Regional Runway Incursion Conference in
Kansas City, the same idea came to me. Rather than weight-actuated
treadle, and not an Engineer by trade, I was thinking of a simple
underground loop detector that would electronically have the same
results.
Has your treadle idea been presented to the FAA, and how long ago did
you come up with it? Would the treadle device hamper snow removal
activity?
Regards, Bob Johnson,
Assistant Manager of Operations Kansas City International
Airport, Operations Division
601 Brasilia Ave
P.O. Box 20047 Kansas City, MO 64095-0047