Posts by Bill Walker


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21) Message boards : Cafe SETI : Slips of tongue (Message 1704751)
Posted 24 Jul 2015 by Profile Bill Walker
A grammatical error.


Let's eat, Grandma.

Let's eat Grandma.

GRAMMAR SAVES LIVES!!!


22) Message boards : Cafe SETI : Don't know where it should go? Stick it here! (Message 1704749)
Posted 24 Jul 2015 by Profile Bill Walker
If we are going for geeky history...

I built my first computer myself in 1966.



Took my first Fortan class in 1970, on an IBM 360. IIRC, it had 640k of RAM, in a case the size of a small fridge. (That's not me in the picture, I looked WAY cooler in 1970.)



I wrote my Masters Thesis on a Wang, in 1984/1985. Figures from Fortan programs run on a Varian, (that the school had just purchased to replace a cabinet sized HP that ran on paper tape) and on a CDC first generation CAD system.

23) Message boards : Cafe SETI : Transportation safety 2 (Message 1704438)
Posted 23 Jul 2015 by Profile Bill Walker

Then it is illegal without another qualified pilot onboard to have "eyeballs out."


You make several good points, there is still much to be found out though. We need a lawyer to reply to that last statement, but if it was illegal why did the tower clear the F-16 to the approach? Why does a published approach have so much of the route in Class E airspace? Surely there would be times when a "legitimate" TACAN approach, in poor vis, would be underway at the same time as some little airplane runs the scud.

If I remember how to read a US Sectional (I usually let my driver do that these days) the Cessna should have been talking to Charleston Approach on 135.8 well before the collision. No indication yet if he was.

And if the collision occurred at approximately 1500 feet MSL, unless the F-16 was WAY too low they were just a few miles from the airport, within the 4,000 feet to surface "cake layer". Don't you need tower permission to enter that? Even if they were in the 4,000 to 1,200 layer, the Cessna was either busting or about to bust airspace.

Another big unknown is the relative flight paths immediately before impact. If we believe the transponder altitudes, the F-16 descended into the Cessna - from above as viewed from the Cessna. There is NO upward vis in the 150, except for a small arc directly in front of the pilot, from many hours of personal experience. Similarly, if the 150 was below the F-16 nose (the F-16 was slowing, increasing angle of attack throughout the approach) the Cessna could have been completely blocked to him as well. That is why I say there are times when "see and be seen" does not and cannot work.
24) Message boards : Cafe SETI : Transportation safety 2 (Message 1704249)
Posted 23 Jul 2015 by Profile Bill Walker

Bill, last I checked, if you were in VMC you still were required to use your eyeballs.


And this is why I dislike commenting on preliminary reports. But since you brought it up... ;)

The F-16 was on a published approach procedure, cleared to the approach by the tower. The tower reported "traffic below you" when he clearly had no way of knowing this.

As to altitudes, with the transponder reporting pressure altitude at 29.92" and weather at 30.15" you tell me which way and by how much the transponder was off, assuming it was still in calibration. A ground school question. Now tell me if the radar the controller was looking at compensates for it?


All good questions. The aircraft setting 30.15 will indicate higher than the transponder. Bigger question: what altimeter setting was in each aircraft? Did the 150 assume he was well clear of the approach path? I'm a little surprised at the statement in the report that the 150 had no need to be talking to the tower. He was obviously very close to a published approach path, should he have been talking to a regional controller? Was he? We don't know yet.

Regardless of the corrections applied or not applied on the controllers scope, and regardless of the calibration and usage of the two transponders involved, the controller's scope indicates altitude rounded to the nearest 100 feet. Calling two aircraft indicating 1400 and 1500 feet "separated" is, I repeat, a huge leap of faith. Added in Edit: The controller also knew the "higher" aircraft was descending, under his control, and had no way of knowing the intentions of the other aircraft, although he should have observed it had a recent history of climbing. That 100 foot vertical separation, even if it was real, was diminishing.

While you are looking up that, what are the regulations on IFR radar separation, altitude and distance. Do those change if the pilot reports VMC and a "practice approach?" The question being was the first call of traffic already after those minimums were broken?


In Canada the controller has a lot of leeway in these calls when the aircraft is under direct control, i.e. cleared to the approach.

Should the jet pilot have called no joy sooner?


In Canada, by law, the controller has to assume no positive response from a pilot is a negative response. I.e., if the pilot says nothing, he doesn't have the traffic. I still question the timing here. The controller has to assume the F-16 will take some time to identify the traffic, and then take some additional time to initiate any corrective action. Given the closing rates, time was not in abundance here.

I can remember another accident very similar to this one in San Diego and both aircraft were talking to the controller and one reported the other in sight. And another in Cerritos. One thing they all had in common, VMC!


And recent history has shown time and time again that VMC plus "see and be seen" simply doesn't work, and can't work, in every situation. That is why we are spending so much time and money on things like multi-layer control zones and TCAS.

The practice approach in VMC is a classic case where this doesn't work. The pilot workload does not allow enough time "eyeballs out". With 20-20 hindsight, the controller should have commanded the higher altitude and higher performance aircraft (the F-16) to abandoned the approach and climb immediately. This would have increased the vertical separation.

Still too many question to draw any real conclusions, IMHO.
25) Message boards : Cafe SETI : Transportation safety 2 (Message 1704148)
Posted 22 Jul 2015 by Profile Bill Walker
I hate to make statements based on a preliminary report, as there probably more facts to come out, but IMHO...

The controller made a huge leap of faith in handing off the situation to the fast mover with such a short time to collision and such a small indicated altitude difference (further facts to come out will include how much indicated altitudes varied from true altitudes, but it seems to have been enough to cause this accident). When the controller stated "traffic below you at 1400 feet" he was implying everything was OK, when clearly it wasn't.

The controller correctly asked the F-16 for confirmation of visual contact, and if it was not received in a timely fashion, he should have issued an avoidance move to the jet in a timely fashion. It remains to be shown that the F-16 pilot had enough time to complete the requested turn, or even if the requested turn would have avoided the collision. The jet was under positive control, literally placing everybody's fate in the controllers hands.
26) Message boards : Cafe SETI : Beet's give us a caption #61 (Message 1703186)
Posted 19 Jul 2015 by Profile Bill Walker
Trick or treat!
27) Message boards : Cafe SETI : C'mon the Aussies, up for it? (Message 1703161)
Posted 19 Jul 2015 by Profile Bill Walker
Hold up there, the Davis Cup
has nothing to do with hockey!


Must be the other sport. What's it called? Oh yeah. Lacrosse.
28) Message boards : Cafe SETI : The train thread (Message 1702648)
Posted 17 Jul 2015 by Profile Bill Walker
In which way are you supposed to turn around those freight trains going end through end across the whole of Canada?


Very carefully.
29) Message boards : Cafe SETI : Beet's give us a caption #61 (Message 1702347)
Posted 16 Jul 2015 by Profile Bill Walker
Pull my finger.
30) Message boards : Cafe SETI : The train thread (Message 1702142)
Posted 16 Jul 2015 by Profile Bill Walker
Here is another shot of North American horsepower to amaze and/or delight you Europeans, taken in 1978. This is a helper consist, making its way down from the summit of Rogers Pass in the Canadian Rockies after helping a west bound freight reach the top. 15,000 hp, all run by two people.

31) Message boards : Cafe SETI : The train thread (Message 1702138)
Posted 16 Jul 2015 by Profile Bill Walker
I found the picture on Facebook, the poster claims the photo was taken recently in Belgium.
32) Message boards : Cafe SETI : Some prayers in need!!! (Message 1701965)
Posted 15 Jul 2015 by Profile Bill Walker
Good news Mike.
33) Message boards : Cafe SETI : The train thread (Message 1701962)
Posted 15 Jul 2015 by Profile Bill Walker
Offered without comment.

34) Message boards : Cafe SETI : Beet's give us a caption #61 (Message 1701710)
Posted 15 Jul 2015 by Profile Bill Walker
The most elaborate sink hole I've ever seen.
35) Message boards : Cafe SETI : Don't know where it should go? Stick it here! (Message 1701707)
Posted 15 Jul 2015 by Profile Bill Walker
You missed a big one Carlos, that sometimes applies to Canadians as well:

Americans/Canadians tell everybody how much they saved when they bought something, never how much it cost.
36) Message boards : Cafe SETI : The train thread (Message 1701327)
Posted 14 Jul 2015 by Profile Bill Walker
Bernie, this talk of turntables has got me thinking about your mysterious turning train. Maybe they are not concerned about which engine is where, but are actually turning the entire train. This means the cars arrive at a station on the return trip in the same order as on the inbound trip. Baggage car always first, first class car always last, etc.
37) Message boards : Cafe SETI : The train thread (Message 1701251)
Posted 14 Jul 2015 by Profile Bill Walker
Canada had lots and lots back in the day as well. A few remain in museums, like this one just north of Edmonton. We stopped using them for the same reason everybody else did: expensive to maintain, and can't turn a whole cut of cars.


38) Message boards : Cafe SETI : The celttooth thread ... AURORAWATCH RED ALERT IN EFFECT (Message 1701129)
Posted 13 Jul 2015 by Profile Bill Walker
Help is on the way Canada, more Ausssie fire fighters are on their way. :-)


Thank you Good Sir, we need the help!



Thanks from me too.
39) Message boards : Cafe SETI : Don't know where it should go? Stick it here! (Message 1701034)
Posted 13 Jul 2015 by Profile Bill Walker
In North America we get clock updates via radio from the US NIST reference clock in Colorado. Like Chris, I have one radio set clock in the house, and set all the others off of it.
40) Message boards : Cafe SETI : The train thread (Message 1700146)
Posted 10 Jul 2015 by Profile Bill Walker
Clearly a junk yard, not a wreck site.


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