Using the phrase 'Heavy' in radio calls

[Irishwingz]

Why does a pilot have to sometimes say their aircraft type and the word heavy afterward? Like 'this is United 747 Heavy'. (i know heavy refers to having a plane load of pax)

Is it used if asked to identify themselves?

Surely if ATC were told 'United 747' they would have a pretty good idea its heavy anyway?

Just a bit curious if its still used and under what circumstances....

Cheers

[HEATHROW DIRECTOR]

It's a reminder to ATC that it is a heavy aircraft and requires extra spacing for vortex wake. It's not mandatory in some countries but ATC often requires pilots to confirm their aircraft type for the same reason. Airlines have a habit of changing the type of aircraft without amending the stored flight plan.

[Irishwingz]

cheers....quick answer.

I'm suprised. I would have thought there was standard spacing mandated no matter if the bird was heavy or not - you know for safety reasons, in case the wake caused the following aircraft some hazard.

[Final 3 Greens]

cheers....quick answer.
I'm suprised. I would have thought there was standard spacing mandated no matter if the bird was heavy or not - you know for safety reasons, in case the wake caused the following aircraft some hazard.

The separation is largely dependent on the aircraft type and the term HEAVY groups together aircraft above a certain mass that would be expected to move a bit of air and need more separation.

There are some lighter aircraft, such as the B757 which are said to punch above their weight in this respect and I'm not a professional, so I can't advise you whether they are added to the heavy category or not.

Perhaps HD will be kind enough to advise.

[Georgeablelovehowindia]

'Heavy' is applied to aircraft of 136,000 kg (300,000lb) mass or more. It's most commonly used in the USA, where the word is appended to the callsign, on first contact on a new frequency.

I don't know if it still applies, but when I flew 757s in US airspace some ten years ago, we were regarded as 'Heavy' for wake turbulence purposes.

[NudgingSteel]

The UK uses four groupings based on aircraft weight - Light, Small, Medium and Heavy. Vortex separation is based on these although ATC don't know the exact weight of each individual flight, so a lightly-loaded 747 is considered to create as much vortex wake as a very heavy one.
Certain 'Medium' types (757, DC8, VC10) as mentioned above create more vortex than other types of the same group (737, Fokker100 etc) and so ATC provide an extra mile behind these when vectoring. 757 in particular is considered almost a special case, as it can produce particularly strong vortices, especially with lots of flap extended. For this reason it is considered a 'Heavy' for ATC purposes in several countries (Germany for one).
Interestingly...an E145 pilot of my acquaintance reckons that 757s don't produce anything like as much vortex in departure configuration as many crews think. He'll happily depart 1 minute behind one, whereas many 737 or A320-type crews often want 2 minutes instead of the UK-approved requirement for none.

er...back to the original question! As HD says, some countries require the 'Heavy' added to the callsign as a reminder to ATC. Although we do have the flightplan details, sometimes aircraft are changed and the details don't get through. A slightly different cruise speed, or a different paint scheme, won't kill anyone. Incorrect vortex separation does.

[PhotoBoy]

IrishWingz,

If I land my Cessna 150 ahead of a 747, the Boeing isn't going to need any more separation than the time it takes me to clear the active runway, as he can punch straight through any amount of air that I could possibly disturb.

However, if I'n coming in behind the 747, I'd like a gap of either 4 minutes or 8nm so as I don't get turned upside down and thrown into the ground by his wake turbulance.

With so many planes in holding patterns, the ATC (and the airline companies) don't want to keep a Jumbo in the air for 8 more minutes than they need to, just on the basis of fuel costs alone.

[Oshkosh George]

I think this will help you enormously,it does NOT matter how heavily loaded the aircraft is!

http://www.airlinecodes.co.uk/acrtypes.htm

[sgsslok]

I thought a Cessna 172 would be "Cessna 172" and a Cessna 172RG would be "Cessna 172 Heavy"?? :confused:

Lok

[Irishwingz]

Hi All

Thanks, here is what I deduce from all the posts...

It seems that I thought saying 'heavy' meant you were carrying pax - which is wrong. I now understand it serves to remind the atc of your weight category and hence how much seperation is needed.

I guess I'll stop using the phrase 'C172 Heavy' now:}