Boeing 737-800/900 wake turbulence category
 

Ok,
I'am flying the Dash-8 for a company in Europe.
Like everybody knows this is a medium (wake turbulence) category airplane.
Now did we get about a year or two ago a writing from our company that behind a B737-800/900 (which is also medium category)we had to keep a wake tubulence seperation of a heavy aircraft. This because an ATR had an wake turbulence encounter behind a 737-800. This means a wake turbulence delay on takeoff from 2 minutes. My company said they came with the writing because of a message from I think Eurocontrol. I tried to find anything on the internet about it but I can not find anything.
Who knows where to find something official about this??

B738/9 Wake Turbulence Category
 

Having controlled in an ICAO state where there were numerous B738's operating - we never received from our regulator/CAA/ICAO any documents/instructions requiring us to provide more separation behind a B738.

We also had DH8C's operating there, and they together with the B738's were both treated as Medium wake turbulence category aircraft...

I honestly do not know about the B739's...

To my knowledge there is no such written rule for Boeings 737/800 or 900, at least in France and from a controller's point of view.

The only thing I know about the B757, which is considered as medium when following and heavy when ahead (again in France as I recall they have some sort of intermediate heavy definition in the Uk).

But anyway, I've had quite a few pilots on ATRs to ask for 2 minutes delays when departing after B737/800 or A321. I asked one why and he answered that it was company rule. That's about it.

Ok,
thank you for your kind answers.
Will look further.

By the way this is the writing we had from our company.

Dated beginning of 2003:
Recently , pilots flying on ATR-72 and similar aircraft experienced moderate
wake turbulence at take-off following a 737-800. As from a flight safety
perspective, the 737-800 must be considered as 'heavy' instead of 'medium',
until further inquiries are made. In addition, at take-off the crew must
request ATC to provide sufficient separation, considering the 737-800 as a
'Heavy' aircraft.