"Level Busts" increasing in UK -- The Times

[shoey1976]

http://www.timesonline.co.uk/tol/new...cle2224956.ece

the above is a link to a piece in the Times today, highlighting a recent sharp increase in the number of level busts.
During my investigation into pilot fatigue, a number of you mentioned level busts as being one classic symptom of fatigue.
Would it be too simplistic to link the two?
I'd be very keen to hear from you -- unfortunately I can't delete messages from my PM inbox - I need to keep them for a while in case anybody has any queries regarding fatigued pilots... so please email or ring me.
Best wishes
Ian Shoesmith
BBC News
020 8624 9505
[email protected]

[Basil]

I've no personal empiric evidence that level busts are fatigue related but it would seem reasonable to look into fatigue as a contributary factor.

I've said it before and will say again:
1. 320 and 330 can sound very similar on RT.
2. If ANY crewmember expresses doubt about the cleared level ask again and keep asking until there is no doubt. If, as an FO, you are flying with 'one of those captains' don't ask him if you should reconfirm with ATC - just do it (he can't then tell you not to). Embarrassment is transient - death is permanent.

[windriver]

Just in case you haven`t seen this here's a Level Bust Website URL

http://www.levelbust.com/

[Spamcan defender]

I dont believe level busts to be solely due to fatigue although I'm sure it MAY be contributary. Many other factors are also involved such as mishearing ATC instructions, correctly hearing ATC instruction and correct readback but inputing wrong level into autopilot etc etc....
The use of Mode S in the TMA has helped a lot in preventing potential busts and its a GREAT piece of kit. Only wish EVERY a/c in the TMA had it.

Spamcan

[hapzim]

I'll second the mode S comment .

Other morning on way in to London TMA the controller gave us a level which we read back correctlly but miss set by 1000' . Within a few seconds the controller was back to us to confirm the level we had set. Mode S system worked a treat and the controller was on the ball (thanks again) watching the screen not just accepting our read back.

[BOAC]

Ian - bottom right of the PM screen is the option to download your messages in various formats. You can then delete to make space.

[breguet]

It would be interesting to know if the level bust were occuring on descent(i,e, when flights from North America are inbound after a night in the air or departing with normally rested crews), then who did the level bust because the accent may be a contibuting factor. Finally, why are they so many level bust in London TMA with respect to other TMAs in Europe. If memory serves well, I do not remember problems anywhere else.....

[mustangsally]

Wonder if the level busts could have anything to do with the floating transition altitude/level. I've always like the fix transition altitude/level being the same on the way up and down.

[AlexL]

Mike, I understand what you say about VNAV, but (correct me If I'm wrong) the mode control panel will always have the cleared level, set in it. the FMC will (i believe) never have a stop altitude in it that is more stringent (lower in a climb, or higher in a descent) than the ATC cleared level.
The FMC may well have some descent and climb criteria (ie below a level by a certain point during descent and vice versa), but surely noone is going to rely on the FMC and VNAV to make sure they stop at the cleared level - that should always be in the MCP.

[fireflybob]

Have any of these level busts occurred when the non flying pilot has been off ATC watch to copy ATIS (especially when said ATIS is on a freq which is being blocked by another station when in cruise before descent) and/or making calls to handling agents for wheelchairs and the like?

[Bealzebub]

Or, whilst attempting to get a clarification request into the gapless "auctioneers patter" that has become the hallmark of London ATCC ?

[bomarc]

wondering?

earlier in this thread, someone indicated that ATC caught a mis-set altitude assignment. this via mode s transponder

I've checked with all my domestic usa airline pilot buddies and to their knowledge this isn't being done in the USA. While the capabilities of mode S transponder are wonderful, I ask if it is a country by country thing right now.

b

[zkdli]

BOMARC,
Mode "S" downlinking of the Selected Flight Level is only availableto London TMA controllers. This unit is the first in the world to have this capability.

[bomarc]

zkldi

thank you

[Airbubba]

Wonder if the level busts could have anything to do with the floating transition altitude/level. I've always like the fix transition altitude/level being the same on the way up and down.

I would say that the low transition altitude and level in the UK contributes to some altitude busts since you reset QNH or QNE in the terminal area at times of high workload and traffic. Also, clearances to levels and altitudes near the transition layer are common, some companies reset the altimeter when a clearance across the layer is received, others wait until crossing the layer lest the controller ask for "passing altitude". Just when you reach for that altimeter knob, you inevitably get a vector or another altitude constraint, it's the nature of the game in busy airspace down low.

In the States with transitions at 18,000 you normally get a less urgent clearance involving an altimeter transition, e.g. out of 12,000 cleared to FL240 or descending out of FL200 cross BOBBO intersection at 11,000 and 250 knots.

[Petruchio]

I think a bigger issue than the TA in the UK is the presence of stepped climb SIDs at a number of busy airports with equally busy GMC positions. First stop altitudes are frequently bust - and I understand that the charts used often don't help in this respect. The DAP policy - if I have understood it correctly - is to harmonise at a common TA inside CAS of 6000ft - outside CAS it will remain at 3000ft...

I thought the Times article (apart from the headline) was pretty reasonable overall....

[AlexL]

I would say that the low transition altitude and level in the UK contributes to some altitude busts since you reset QNH or QNE in the terminal area at times of high workload and traffic. Also, clearances to levels and altitudes near the transition layer are common, some companies reset the altimeter when a clearance across the layer is received, others wait until crossing the layer lest the controller ask for "passing altitude". Just when you reach for that altimeter knob, you inevitably get a vector or another altitude constraint, it's the nature of the game in busy airspace down low.

I was always taught, that when cleared from an alt to an FL, or vice versa that you reset the altimeter BEFORE starting to climb / descend, to avoid just this sort of problem.
Obviously if the initial departure clearance is to an FL then one needs to remember to set QNE, but I can't see why one would have to wait till actually passing the transition level? in any case you have the standby which will probably be on QNH anyway, in order to read back a passing level if required.
Anyhoo - re the increase in level busts - is this due to LATCC changing their reporting criteria last year? or maybe trying to squeeze a quart into a pint pot is finally causing the system to creak at the seams?

[Airbubba]

I think a bigger issue than the TA in the UK is the presence of stepped climb SIDs at a number of busy airports with equally busy GMC positions. First stop altitudes are frequently bust - and I understand that the charts used often don't help in this respect.

I agree, some of those departures are spring loaded for a bust with complicated hairpin turns, at or above and at or below and mandatory altitude constraints and speeds just as you are trying to get a heavy (or sometimes, even worse, light) aircraft cleaned up and accelerating. And, don't forget to set QNE at the low transition altitude, deal with the altitude captures and comply with local noise abatement etc.

There are a few wacky U.S. departures but even at the largest airports many departures are simple vectors with a climb to 5000 feet. This gives you time to concentrate on flying the plane in those critical first couple of minutes.

[Current Limiter]

Level Busts

I heard the other day a stasistic that between 70 to 80percent of aircraft operating within UK airspace are flown by crews where english is not their first language. CAP371 - a radiotelephony document introduced to try and improve safety by raising RTF standards, especially wrt level busts, seems only to be applied fully in the UK airspaces.

Only once all aircrews operating into this busy airspace adhere to and understand the importance of using these procedures, will there be progress in limiting level busts.

Combine these two points with very busy RT, pilot fatigue after long flights, and tricky arrivals/departures with step clearances, then no wonder level busts still occur.

[Current Limiter]

Correction on the CAP - that should be CAP413....