Forum Topic

Increase in Heathrow Trial flights last weekend

The daily results from Saturday and Sunday have gone up on heathrowtrial.com and showed much larger numbers of TEAM* flights.Saturday 3rd DecemberTotal number of TEAM* arrivals on westerly operations after 0700hrs local time 45Sunday 4th DecemberTotal number of TEAM* arrivals on westerly operations after 0700hrs local time 41On the Saturday, under the northern runway I noticed "out of alternation" "in the respite period" overhead flights at 7:58 ,8:26, 8:33, 8:52, 9:11, 9:36, 9:53, 10:34, 10:41, 10:54, 11:05, and 11:30.The daily reports also show that the complaints on Saturday increased to 17.Although the operational freedom trial flights appear to have increased sharply, the total number of TEAM flights (including those done under "current operating criteria" - whatever those are) has not changed massively. Perhaps there has been a decision to change the reporting method ?

Tim Henderson ● 4993d2 Comments

"The "current operating criteria" are that flights can be switched to the alternate runway if delays in the holding stacks exceed 20 minutes."I have been trying to get BAA to confirm the "current operating criteria" for some time and they appear to be coy about publishing them. I sense that they may be embarrassed to the extent to which TEAM has been used of recent years . Since it was originally introduced as a "tactical" measure to be employed on rare occasions, it has increased to being routine and the value of it as a tactical option has been eroded as flight scheduling now relies on it and capacity becomes more awkward with increased numbers of larger planes requiring greater separation distances.Appendix E of the Adding Capacity consultation (archived athttp://collections.europarchive.org/tna/20080305120253/http://www.dft.gov.uk/consultations/closed/heathrowconsultation/consultationdocument/annexe.pdf)presents some carefully scripted background"When severe inbound congestion occurs in the air, or is likely to occur, involving delays of 20 minutes or more, NATS has the discretion, if weather and other operational factors permit, to land additional aircraft on the departure runway if it considers the landing rate can be increased. Aircraft may also land out of alternation during runway closures. However, the airport still manages to use alternation for around 95 per cent of the time."The daily report at heathrowtrial.com for 29th November had this figure plummet to 76.40%. Other daily reports show the maximum time spent in the stack as being 17 minutes, yet considerable numbers of TEAM flights were flown. The evidence that without this intervention delays would have exceeded a particular value is not yet presented. It is not clear what authority granted the discretion to NATS or what agreed process determined the trigger level at which TEAM should be invoked. I have the impression that BAA would prefer not too much light be shone on the matter.It is interesting that the CAA consultation on a scheme to reward NATS financially for increasing flight efficiency ends today. One hopes that without independent regulation NATS judgement as to when delays "are likely to occur" and TEAM is to be invoked will not be clouded by the consideration of their bonus.

Tim Henderson ● 4992d

"Although the operational freedom trial flights appear to have increased sharply, the total number of TEAM flights (including those done under "current operating criteria" - whatever those are) has not changed massively."Interesting.  The "current operating criteria" are that flights can be switched to the alternate runway if delays in the holding stacks exceed 20 minutes.  Once that condition has been reached, it may take a number of TEAM arrivals to clear the backlog.  During the trial, or at least those periods when this criterion is varied, TEAM arrivals can be used if delays reach 10 minutes.  Maybe the earlier option of using TEAM arrivals helps to prevent backlogs building up, so that the TEAM total is not much increased.

Richard Jennings ● 4992d