Peter wrote:
Sorry, have just the phone today. Was it radiating mode C?Yes. The report included radar pictures of the airmiss showing both aircraft. The C42 was squawking 7000 and the correct altitude.
So why did the jet pilot not heed the (presumed) TCAS warnings? Will it be possible to verify whether his statement that he had no TCAS alert was correct?
For the rest, this report shows all the mess of the disjointed UK ATC system.
So why did the jet pilot not heed the (presumed) TCAS warnings?
Maybe he didn’t get one? There are many possible reasons. Setting the transponder to ALT only (instead of TA/RA) for example. Within uncontrolled airspace and especially in traffic patterns one tends to get frequent traffic alerts. Depending on company SOPs one has to react to them (which would mean that one could never land at a busy VFR airfield…) and write a report every time. Or the TCAS system, which is programmed quite smartly, has concluded that there was no real threat of collision. From the video I can’t really tell. TCAS will not shout out a warning every time another aircraft passes close by – only if a collision is “geometrically” imminent.
Will it be possible to verify whether his statement that he had no TCAS alert was correct?
No. Unless not more than 2 (battery on) hours have passed since the event and the pilot(s) agree that their CVR and FDR recordings are downloaded and analysed. There was no accident (and probably no “incident” either) which means no authority can enforce to obtain the flight data.
Anyway, for me this is the typical “storm in a glass of water” over something which is rather common in this kind of operation. And it wasn’t even close.
The ‘pilot’ of the Citation must have been a nut to unnecessarily leave controlled airspace that early and tear VFR across the countryside at 240 kts, it may be legal but its hardly very intelligent, maybe he is happy to kill himself but what about the safety of innocent passengers, other pilots and persons on the ground ?
quatrelle wrote:
The ‘pilot’ of the Citation must have been a nut to unnecessarily leave controlled airspace that early …
Do we know whether or not he left controlled airspace out of his own will? I don’t remember having read anything in that matter in the airprox report. If I remember correctly he was on a standard arrival route into Biggin which led through uncontrolled airspace… It is my own experience in the UK that while you are on a STAR (always way too low and way too early for a jet!) you are suddenly told “you are now leaving controlled airspace – which service do you request?”. My immediate reaction is always to answer “request to re-enter controlled airspace” but obviously this is not an option.
In Germany I always try to climb at maximum rate to FL100 (where uncontrolled VFR flying ends) and stay as high as possible for as long as possible when flying the jet.
The pilot of the Citation was no more a nut than the crew of the C42….or any military jet pilot for that matter.
airways wrote:
The pilot of the Citation was no more a nut than the crew of the C42
Really??…. outside controlled airspace you should expect to see a C42 pondering around the sky not a lunatic in a Citation not looking out for other traffic.
what_next wrote:
If I remember correctly he was on a standard arrival route into Biggin which led through uncontrolled airspace
We have all been ‘Dumped at Detling’ if going into a smaller airfield but London Control would never dump you at Eastbourne on a STAR inbound to Biggin, it must have been the pilots own choice
outside controlled airspace you should expect to see a C42 pondering around the sky not a lunatic in a Citation not looking out for other traffic.
Bizjets often fly in Class G. They have no choice, for most GA airfields.
London Control would never dump you at Eastbourne on a STAR inbound to Biggin, it must have been the pilots own choice
I have just had a look at the Biggin STARs and while I don’t know typical ATC-directed levels, they seem to be a lot in Class G. The normal procedure from when I have been Eurocontrol-IFR to Biggin (or even “UK Class G IFR”) is to get handed to Thames Radar for approach vectoring (Biggin have a deal with them because they pay them some hefty fee for the radar service).
However you also get a lot of GA flying through IAPs in Class G – as PPLs they were mostly never taught about this. So you are just as vulnerable flying the ILS into Biggin; the main “protection” comes from the fact that in bad wx the traffic density falls dramatically, to near zero in IMC.
I thought a “Basic Service” was just the “Area QNH” and replay the record of your communications to the SAR and AAIB if you disappear. 
I benefitted in US Class G from an alert to a near collision – my C172 and a Pa28 200’ above me, both descending, and never visual with each other, in excellent visibility.
Peter wrote:
However you also get a lot of GA flying through IAPs in Class G – as PPLs they were mostly never taught about this. So you are just as vulnerable flying the ILS into Biggin; the main “protection” comes from the fact that in bad wx the traffic density falls dramatically, to near zero in IMC.
Uncontrolled Class G airspace is not the issue there. No separation from VFR traffic applies in anything below Class C so all traffic in Class D or lower needs to be providing their own separation unless in IMC, where VFR traffic is prohibited. I think this can be a problem for airline and biz jet traffic as they often have no idea in which classification of airspace they are flying. That’s arguably negligent but pragmatically true – If I see an airliner or other jet in (say) Class E airspace I assume they are not watching for traffic as they should, and that ATC may not call me as traffic for them.
