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Guest Ohio330

Heavy?

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Guest Ohio330

Sorry for the ignorance, but what does HEAVY mean when refering to a plane? Just wondering because I hear other pilots on Vatsim calling this out when they give their callsigns. Was just wondering what determines whether or not a plane is deamed a "heavy". Thanks.-Adam Harmon

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Adam,I am no real expert, but here is what I understand.It's all about aircraft spacing. A large aircraft creates a large displacement of air, so it takes longer for the air to stabalise behind the aircraft. So when controllers are spacing aircraft for finals and takeoff etc, they leave a longer time/gap behind a "heavy" aircraft.Another factor is engine blast. If you taxi a small Cessna close behind a 744, then your into big problems, so spacing needs to be adjusted.An interesting example is the 757, although not a particularly large aircraft, it has very powerful engines, so in some countries it is given the "heavy" designator.I hope my expanation helped, and if it was incorrect, could some of the more knowlegable forum members step in and correct me.Thanks,Paul

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HI !The suffix Heavy is refered to the MTOW of the plane for the wake turbolence. For separation from other traffic. here is the weights of the planes and the suffix to be usedH: Heavy (MOTW of 136.000 kg (300.000 lb) or higher ); M: Medium (MOTW between 7.000 Kg (15.500 lb) and 136.000 kg (300.000 lb); L: Light (MOTW of 7.000 kg (15.500 lb ) or less).


Alfredo Russo

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Guest Ohio330

Oh, ok, thanks for the info. I was just curious how they specifically (in the USA) label a specific craft. I.E. anything heavier than, say, 125,000lbs. empty weight, etc. etc. I didnt think of the factors you used. I was thinking it probably had to do with basically letting a controller know that the particular aircraft is going to need a longer runway. Im planning on using a lot of different craft in Vatsim and want to get a handle on whether I need to call it "heavy" or not. Thanks!

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Guest Ohio330

Great thanks! I assume MOTW means the total weight of the craft plus fuel, cargo and passengers?

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Paul,You are pretty much spot on. The 757 actually gets a special notification by FAA for its configuration, as much as its power. The issue is still debated as the FAA/NTSB/NOAA/AOPA (and just about everyone else), each seem to have different data and agendas. The wake discussion stems from an incident where a Westwind bizjet "rolled" into the ground due to wake vortices generated from a 757. It seems that the configuration of the wing/flaps/powerful engines(spaced relatively close together) makes for a wicked wake effect. I believe that, that caused the FAA to make the decision to treat it just like a true "heavy" (+300,000lbs) jet, and require extra seperation.BestBill"The only time an aircraft has too much fuel on board is when it is on fire." -- Sir Charles Kingsford Smith

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Guest matsuman

Is the B2 bomber consider as "heavy"?I thought some other specifications are base on the wing size, because of the wake turbulance that it generates.Kin M.(KLAX)

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In the US anything over a MTOW of 255,000 pounds is considered a heavy. Believe it or not, even the 757 is a heavey, wake turbulance or none. Both the 752 and 753 have a MTOW of 255,000 pounds or more.


Mike Roth

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If you want to learn more about wake turbulence, and ATC addressing this subject, go to faa.gov and look in the Aeronautical Information Manual (AIM). Chapter 7 (Safety) talks a lot about this subject.BestBill

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Hi there allIs 'heavy' spoken outside the US?CheersRudy


Rudy Fidao

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Actually it's anything over 300000 lbs. The 757 is in a special catagory by itself. We treat the 757 just like a 747. 5 miles spacing with everything but a small which gets 6. Also, with the 757, it has nothing to do with the engines. It's all about the vorticies off the wings. They also rolled a Citation who was trailing too close. One other thing. Only towers and approach controlls (TRACONS) in the US use the phrase "Heavy". The Centers (ARTCCs) no longer say this. Scott


Kendall S Mann

Still Telling Pilots Where To Go!!

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Yes, heavy is used all over the world, but here in Europe atleast it's only used on initial call and not after every like in the US.

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>Actually it's anything over 300000 lbs. The 757 is in a>special catagory by itself. We treat the 757 just like a 747.>5 miles spacing with everything but a small which gets 6.>Also, with the 757, it has nothing to do with the engines.>It's all about the vorticies off the wings. Two questions. One, since I see you say it's anything over 300,000 lbs, why is it the .65 states,"AIRCRAFT WEIGHT CLASSES a. Heavy. Aircraft capable of takeoff weights of more than 255,000 pounds whether or not they are operating at this weight during a particular phase of flight."sure looks like anything over 255,000 pounds to me? Did they change it, and just not update the .65?Two, if it is indeed 255,000 pounds, which is what I've always been told, and what I read the .65 to show, why does it matter if the 757 has it's own class. According to Boeings website, both the 752 and 753 have a MTOW of 255,000 pounds or greater which would put it in the heavy class regardless.EDIT: Note, I'm not doubting you, this is just something I've seen discuessed many times and I find it interesting. Just curious where the 300,000 pounds comes from.


Mike Roth

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