What's My Aircraft Type?

[V1]

Can someone explain why is it that the only ATC unit that asks me for my aircraft type is the Approach Director at my home base in the UK?! …..Which I have generally only left a few hours previously!

By the time I’ve passed: Call sign, Heading, Cleared Level, Speed and ATIS designator I’ve already used up quite enough airtime in the busy London Airspace without then having to remind ATC what my type is as well.

Is this REALLY necessary? Surely this is on the flight plan/strip that you have in front of you, and why is this information only required in the UK?

[eglnyt]

There is an aircraft type on the strip in front of him but until you tell him your aircraft type he has no way of telling whether or not it's correct. You're about to enter a phase of the flight where bad things can hapen if it's wrong.

[paperclip810]

It's procedure for all of the major London airport approach units to verify the aircraft type of those inbound.

Although the strip should reflect any changes made to the flight plan as far as aircraft changes go, the strip can be wrong. Wake turbulence separation must be provided on final approach, so this is the concern of the approach director.

If we have the wrong aircraft type on our strip for any reason, and then vector you straight into some wake turbulence, it's not very safe and you won't be happy!

Hope that helps.

[aerotech07]

And to illustrate the point, for example if an operator uses both ATR42 and 72, or Fokker 70 and 100 they may substitute aircraft for operational reasons and for whatever reason the flight plan never gets the update.

Both those aircraft series span 2 wake turbulence categories, and there are operators who do fly them and do substitute. Its not unknown for the flightplan and strip to be wrong.

[ATC Watcher]

and for whatever reason the flight plan never gets the update.
One is called repetitive FPLs, some filed 6 months in advance.

[Talkdownman]

Is this REALLY necessary?
As verification for critical flight safety reasons, yes.
If other countries do not do it then that is their lookout, and maybe their loss.

[aerotech07]

One is called repetitive FPLs, some filed 6 months in advance.

I appreciate that, although most times when equipment is substituted the FPL gets updated, even when it originated as a repetitive plan.

[ex-EGLL]

I appreciate that, although most times when equipment is substituted the FPL gets updated, even when it originated as a repetitive plan.

It's the "non-most" times where the problems occur!

[10 DME ARC]

As all of the above to give you an example just yesterday I had an aircraft check in "XYZ123 a B773 with Xray" the strip said A320!! If I had put a medium three miles behind what I thought was another medium!!! :uhoh:

[DFC]

Here we have a clasic case of trying to brush a problem under the carpet and failing to recognise the wider picture.

How many reports are submitted when the aircraft type on the strip matches the flight plan but does not match the type used for ther operation?

R/T loading is the least of the problems.

What about the flight profile not matching the type and thus the flight receiving a no delay when the actual profile would have picked up a CTOT?

There is one flight plan for every flight. Provided that the aerodrome control unit at the departure point does it's job then we should not have the case of any unit along the route expecting an ATR when the flight is being operated using a FK100.

Operators are required to keep the flight data up to date and that includes filing a CHG or CNL/FPL when the details don't match the RPL.

While I don't see a problem with reporting type on initial contact and agree that it is a safety issue, I would love to hear how many times per day/week/month/year a different type turns up and based on that data what is being done to educate operators and ATS units.

[HEATHROW DIRECTOR]

DFC.. If I had a pound for every time I had a "wrong type" caused by the operator not informing ATC I would be very rich - and I am NOT joking one bit.

How many reports are submitted when the aircraft type on the strip matches the flight plan but does not match the type used for ther operation?

I can't speak for what happens now, but when I was working the ATC system was updated but nothing else.

What about the flight profile not matching the type and thus the flight receiving a no delay when the actual profile would have picked up a CTOT?

Don't know what you mean as the type has little bearing on this, assuming the "right" one and the "wrong" one are of similar performance.

There is one flight plan for every flight. Provided that the aerodrome control unit at the departure point does it's job then we should not have the case of any unit along the route expecting an ATR when the flight is being operated using a FK100.

The aerodrome control unit where I worked did do its job and that is precisely why ATC require pilots to state their aircraft type.

Lastly, you would not believe it but pilots are not beyond giving the wrong type on the R/T. Incredible, but true.

[reportyourlevel]

As for the aerodrome of departure doing it's job, can you tell the difference between an ATR 42-300 (light) and an ATR 42-500 (small), at the other side of the airport in the dark? Thought not.

[DFC]

As for the aerodrome of departure doing it's job, can you tell the difference between an ATR 42-300 (light) and an ATR 42-500 (small), at the other side of the airport in the dark? Thought not.


I think that you will find that all of the ATRs - the 42 versions and the 72 are within the ICAO Medium wake category. Therefore, in terms of wake turbulence there would be no change to the flight plan. Perhaps you could pick a relevant example?

If you get a call from ABC123 for clearance, an A320 on stand 99 with information "A" and you look at your fps and see that the flight is filed as an ATR then you can refuse clearance until the change is reflected in the flight plan - or you can tramsmitt the change message and give the clearance.

Either way, it is the aerodrome of departure that has the best opportunity to pick up the error - day or night.

------

Don't know what you mean as the type has little bearing on this, assuming the "right" one and the "wrong" one are of similar performance.




I wasn't assuming. If the flight plan says B737 and a B777 operates the route then there are a number of performance and other issues.

The CFMU profiles flights and uses lots of data to calculate sector load. With a CTOT based on the slower speed a CTOT can be avoided but travelling faster than predicted on the flight plan can in a few cases result in the flight(s) arriving early in a sector to be part of the reason for an overload. Lots of work has been put into keeping to the filed level, no short-cuts and related issues and this is simply another part of the system that needs to be tightened up.

but when I was working the ATC system was updated but nothing else.



You and I both remember when a "Just to advise you that your company filed the flight as an ATR42" to a B737 pilot would result in some form of a quip and a message to the company about the flight plan. These days it is simply "roger" 'what is he talking about?' 'never mind back to the newspaper'

[GAPSTER]

30 years in TWR/APP.Numerous examples of a/c type changes leading to a wake turbulence change not reflected on my strip.I get it wrong I get in trouble and lots of other people possibly get into worse trouble...can't believe a pilot can not see the point.

Bottom line,if you don't tell me your type I ask...live with it.

[samotnik]

I think that you will find that all of the ATRs - the 42 versions and the 72 are within the ICAO Medium wake category.

But on the islands they have a bit different wake turbulence categories and separations minimas... ;)

[Denti]

It is just one of those little "british" peculiarities that you simply have to live with. The rest of the world can happily lives without it, but that doesn't really matter, if you fly there, follow their rules.

[reportyourlevel]

I think that you will find that all of the ATRs - the 42 versions and the 72 are within the ICAO Medium wake category. Therefore, in terms of wake turbulence there would be no change to the flight plan. Perhaps you could pick a relevant example?

GAPSTER is right and I stand by my example. I'm not checking your flight plan, I'm checking my strip so I can apply the relevant departure or arrival spacing to ensure you don't get flipped upside down by the one in front. If the type is wrong on my strip, I'll get it changed.

The computer works out which UK category the type falls into and prints it on my strip and also inserts the correct ICAO one on the flight plan, which is then sent to the other relevant ATC units. Their computers will do the conversion in reverse if they are in the UK, printing the correct UK category on the strip. The ICAO category contained in the FPL is therefore irrelevant for a UK domestic flight as all of this is picked up from the type field (assuming all the computers work like ours does - not unreasonable). If your arguments are correct, then why do we bother with the type field at all?

[DFC]

I am aware of the local UK wake categories. However, the point being that these are not used on the flight plan and it is only locally that the type is paired with a different wake category.

As a pilot I am very aware of the UK differences - and would not hesitate to file an MOR if I had a wake encounter that was possibly as a result of these local adjustments to the ICAO categories which operate not just on a national basis but in some cases are only applied at specific airports.

Thankfully there is a European Directive landing on the desk of ATS standards that requires the UK ATS Authority to align it's procedures with ICAO as an interm measure prior to the introduction of European ATS Requirements. Let's hope a few of these "local differences" can be weeded out.

However, as I said previously, while I have no problem providing any information requested at any time in the flight, I do feel that it is simply ignoring the bigger picture.

You may not be aware but the crew are required to have a copy of the filed ATS flight plan onboard - and having a copy of the ACK is normal in most companies. Therefore, it says a lot about the B737 PIC that departs on a flight plan for an ATR - what else did they not check on the paperwork?

[ClimbSequence]

I guess the ATC won't bother to ask when a Ryanair flight checks in

[Talkdownman]

pilots are not beyond giving the wrong type on the R/T. Incredible, but true.

Usually the dual rated 757/767 crews who forget what type they are flying. Not unusual to stuff a 757 two and a half behind another 757, transfer to TWR who then phones down to say that the first 757 is, in fact, a 767....

[Gonzo]

DFC,

As a pilot I am very aware of the UK differences - and would not hesitate to file an MOR if I had a wake encounter that was possibly as a result of these local adjustments to the ICAO categories which operate not just on a national basis but in some cases are only applied at specific airports.

Are there differences between airports now?

Thankfully there is a European Directive landing on the desk of ATS standards that requires the UK ATS Authority to align it's procedures with ICAO as an interm measure prior to the introduction of European ATS Requirements. Let's hope a few of these "local differences" can be weeded out.

Ironically, the RECAT project to reclassify wake vortex categories has proposed a six category system that looks very, very similar to that which we in the UK already use!

[ATCast]

I think it would not be not too difficult to implement a check in the flight data processing system that verifies the actual aircraft type based on the ICAO 24 bit address in the Mode S replies / ADS-B squiters. The data is there already, all that is needed is a database that links the 24 bit address to the aircraft type and there you go. Maintaining that database up to date is of course critical for such a system to work.

ATCast

[HEATHROW DIRECTOR]

ATCast.. Have you seen how inaccurate some of the info from ADS-B is? Hex codes are not 100% accurate by any means.

Is it really a major problem for a pilot just to say "737"? I think not!

[055166k]

Experience in the UK has shown that it is beneficial to vary from the ICAO wake turbulence separation standards.....the UK uses 4 rather than 3 categories generally. Consider the need to maximise runway utilisation at a busy airport such as Heathrow which is bursting at the seams capacity-wise...and which is almost unique in the UK for dual runway operation. Whereas Approach at a single runway operation might use "gaps" to get departures away, Heathrow has a dedicated arrival runway. In order to maximise landing efficiency there is a unique sub-categorisation for wake separations.....for example "upper medium".....this allows a phenominal increase in landing rate whilst still providing adequate safety. I don't do Heathrow Approach except in abnormal circumstances.....hopefully one of our Heathrow colleagues can correct any errors that I've made....and elaborate further on the categories. You can appreciate how vital it is to know exactly which type and/or model of aircraft you are flying. VISIT US AND SEE!!!!

[ATCast]

@ HEATROW DIRECTOR

Is it really a major problem for a pilot just to say "737"? I think not!I wouldn't think so at first, but after reading your previous post:

you would not believe it but pilots are not beyond giving the wrong type on the R/T. Incredible, but true.I started thinking about possible solutions to this waste of comms bandwidth and potential safety hazard.


Have you seen how inaccurate some of the info from ADS-B is? Hex codes are not 100% accurate by any means.I am aware that hex codes are not 100% accurate, nor is anything else in surveillance. In civil aircraft the accuracy is I guess above 99%, military is lower. If you start using the hex codes for this purpose, the percentage will rise when you give feedback to the operators.

Sightly off topic:

Not sure to which inaccuracies in ADS-B you are referring to. There are quite a few aircraft that send inaccurate position, but they indicate that they do so and therefore can be identified as non-suitable ADS-B targets.
Few installations send misleading data. But there is improvement and I am sure that the wrinkles will be ironed out after the EC decides on the mandate for ADS-B in Europe.

Best,

ATCast

[tc_atco]

This is an example of playing off the risk of assuming the filed type is correct versus the potential for frequency congestion and some mild controller/pilot RT irritation.

The much greater risk is that the filed type is incorrect, and the safety implications this would result in. There's lots of ways we could cut down on RT time but the efficiency gain on the RT would be negligible compared to the safety benefit we'd surrender.

In an ideal world all filed plans would be correct, but some aren't and therefore currently the most robust and also the cheapest way is to get you to report it on the RT. If the RT congestion is so bad the controller should split the sector to relieve the pressure.

Type changes are passed onto the tower so they can ensure their conditional clearances are accurate, and I think some stands can't take certain types? Maybe someone who can see planes at their place of work can answer that one.

[HEATHROW DIRECTOR]

ATCast. With the availability of various magic boxes permitting Joe Public to watch "radar" on his PC, several enthusiasts web sites have sprung up dealing with matching hex codes against aircraft registrations, etc. Considering the extremely high integrity of SSR I think you might be surprised at the poor integrity of Mode S information as far as hex codes go and positional inaccuracies with ADS-B are a daily occurrence. Take a look at this picture of an SBS display yesterday.

MSR777.jpg :: Other subjects :: Fotopic.Net (http://www.brendan-mccartney.fotopic.net/p68477386.html)

At the time the picture was recorded, MSR777 was actually established on the ILS about 7nm behind the one ahead. This is not a one-off, but one of anything up to a dozen in one day I have seen. Airline and type are irrelevant but whether particular aircraft always display this problem I do not know.. Safe to say that from the ATC aspect, I imagine that this would be unacceptable.

I'm very interested in this subject and would be glad to hear more..

[eglnyt]

I'm very interested in this subject and would be glad to hear more..

The thread is drifting a bit but search the Eurocontrol site for Cascade and look up Validation and you'll find loads on the subject. Positional inaccuracies with ADS-B are a daily occurrence but the Eurocontrol data shows that these aircraft are also indicating that the position report is of poor quality. Does the SBS box display the quality indicator ? Unless the aircraft is flying in mandatory ADS-B airspace it is not obliged to transmit accurate reports or be equipped to do so.

[Bagheera]

Type changes are passed onto the tower so they can ensure their conditional clearances are accurate, and I think some stands can't take certain types? Maybe someone who can see planes at their place of work can answer that one.

A good point there tc atco. The stand allocation system at my airport works off flight plan data. There are a number of stands that will fit a B735 but not a B738 or a B762 has turned out to be a B763 and a hasty call to airfield ops has had to be made before the back of stand road gets blocked by a stuck out rear!

[HEATHROW DIRECTOR]

Unless things have changed, at most major UK airports ATC has nothing to do with stand allocation which is a matter for the airport authority and the airlines. I believe that the prime purpose of requiring pilots to state aircraft type is wake turbulence separation..

[Mad As A Mad Thing]

It's not just wake turbulence and stand allocation problems. Both of which are very real safety matters, but also if the type hasn't been changed on the flight plan then the whole flight profile has possibly been filed with the wrong levels & speeds too. This could mean that the flight details don't even arrive at the sector you are expecting to fly through as you are flight planned into a different (lower or higher) sector.