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.html 

http://www.pprune.org/cgibin/ultimatebb.cgi?ubb=get_topic&f=6&t=001179 

regards 

IASA Australasia 

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