Narrative:

We were number two for departure; runway 31L. We were following a boeing 767. I instructed my first officer (first officer) to ask for separation behind the 'heavy departing in front of us'. The controller seemed to be confused/annoyed over our initial and subsequent requests. I then asked 'what is standard separation behind a heavy?' the response was 'behind a B767 it's 3.5 miles.' my recollection of [company] flight manual...was five miles. Not wanting to start and argument with the controller...we accepted takeoff clearance and departed when I; as the pilot in command; deemed it safe to do so. After departing and level at cruise altitude; I referenced [company] flight manual. According to aim 7-3-9; separation between a large...and a heavy is five miles. The following day I called jfk tower hoping to speak with a tower supervisor who was unavailable at the time. I did speak with the controller who answered the phone and was informed that the controller we dealt with was; in fact; in compliance with 7110.659 which allows tower controllers to reduce wake turbulence separation between certain aircraft. This information is not contained in our operating manual. During our conversation the controller informed me that 7110.659 was initially implemented at certain airports with the intent of making it effective at all airports which; to his knowledge; had not yet been done.... It raises the question in my mind; is the purpose of 7110.659 to help facilitate traffic flow at the expense of safe wake turbulence separation? Wake turbulence events have been significantly reduced over the years as a result of wake turbulence separation which was initially measured in minutes but reduced to miles (radar separation) and apparently; under this new program; has now been further reduced. Is 7110.659 safe; or just more conducive/accommodating to high traffic airports? Update operating manual to reflect 7110.659.

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Original NASA ASRS Text

Title: Air Carrier Captain questioned the safety of implementing Wake Turbulence Recategorization separation standards at JFK and other major airports.

Narrative: We were number two for departure; Runway 31L. We were following a Boeing 767. I instructed my First Officer (FO) to ask for separation behind the 'Heavy departing in front of us'. The Controller seemed to be confused/annoyed over our initial and subsequent requests. I then asked 'what is standard separation behind a Heavy?' The response was 'behind a B767 it's 3.5 miles.' My recollection of [Company] Flight Manual...was five miles. Not wanting to start and argument with the Controller...we accepted takeoff clearance and departed when I; as the Pilot in Command; deemed it safe to do so. After departing and level at cruise altitude; I referenced [Company] flight manual. According to AIM 7-3-9; separation between a Large...and a Heavy is five miles. The following day I called JFK Tower hoping to speak with a Tower Supervisor who was unavailable at the time. I did speak with the Controller who answered the phone and was informed that the Controller we dealt with was; in fact; in compliance with 7110.659 which allows Tower Controllers to reduce wake turbulence separation between certain aircraft. This information is not contained in our operating manual. During our conversation the Controller informed me that 7110.659 was initially implemented at certain airports with the intent of making it effective at all airports which; to his knowledge; had not yet been done.... It raises the question in my mind; is the purpose of 7110.659 to help facilitate traffic flow at the expense of safe wake turbulence separation? Wake turbulence events have been significantly reduced over the years as a result of wake turbulence separation which was initially measured in minutes but reduced to miles (radar separation) and apparently; under this new program; has now been further reduced. Is 7110.659 safe; or just more conducive/accommodating to high traffic airports? Update operating manual to reflect 7110.659.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.