Commercial Fixed Wing
Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 6.0
Distraction; Workload; Situational Awareness
ATC Issue All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Issued New Clearance; Air Traffic Control Separated Traffic
Company Policy; Chart Or Publication; Procedure
JFK was departing Runway 4L/31L. Aircraft X departed Runway 4L on the correct departure profile which is fly runway heading to the JFK 1.5 DME then turned right heading 100. I cleared Aircraft Y for takeoff when I was assured that he would have appropriate wake turbulence separation with Aircraft X. I switched Aircraft X to departure after I observed his turn and no conflicting traffic for Runway 4R; then turned my scan to the departure off of Runway 31L to switch him to departure; then checked the extended final for Runway 4L. As I turned back to the left to check Aircraft Y I saw that he had turned very early. When I looked out the window; he was passing YA intersection of Runway 4L and already well-established in the turn. Most aircraft; including Aircraft X; don't begin the turn until a half mile off of the departure end of the Runway or so. Had Aircraft Y flown the expected profile; I would have had separation; but as it stood with Aircraft Y turning at least a mile early; I lost separation between the two aircraft. I issued Aircraft Y a 060 heading to peel him off of Aircraft X but also to protect for a missed approach off Runway 4R. I also tried to get Aircraft Y to get the Aircraft X in sight so I could establish pilot-applied visual separation; but as Aircraft Y was in the turn; I tried calling traffic to him and he was having difficulty getting the traffic in sight. When I had re-established my 3 miles of wake turbulence separation; I turned Aircraft Y to a 100 heading and switched him to departure.This is yet another example of pilot misinterpretation of the confusing departure procedure from Runway 4L. Since the FAA refuses to publish this SID as it is expected to be flown by pilots; so that pilots have a very clear and unambiguous SID plate to consult; they are sent a compressed clearance via PDC or CPDLC that has shown time and time again to be confusing to pilots. I find myself advising a pilot at least once or twice a shift before I switch them to departure that the DME referenced in their clearance begins from the JFK VOR and not the arrival or departure threshold of the runway. These [reports] will not cease until the FAA publishes the SID as they expect it to be flown; instead of using some absurd excuse about how we cannot publish the departure procedure that we actually use because 'they haven't done the noise abatement assessment so they can't publish it for legal reasons. But it's ok to continue using it in practice as long as the general public doesn't have a physical document to reference.'  What kind of absurd skewed environment do we work in that the FAA finds it acceptable to publish a departure procedure that we cannot use; but instead are forced to issue a verbal correction to the published procedure to each and every departing aircraft?We cannot issue the JFK5 departure to aircraft off of Runway 4L because we have to protect for the missed approach off of Runway 4R; but we're going to keep publishing it anyway and make the controllers read and have pilots comply with a convoluted and confusing departure procedure that is so super-secret that you just call me on clearance and I'll give it to you verbally. At one of the busiest airports in the world.  With the highest percentage of international traffic in the NAS. Instead of publishing the JFK5 departure procedure off of Runway 4L to include what we actually send these aircraft via PDC and CPDLC and issue by voice; instead I suppose that we will just continue; for years and years and years; to issue a 'JFK5 departure except' clearance to [International Airlines] and the litany of international; English-As-A-Second-Language pilots and cross our fingers and hope that incidents like this get swept under the rug instead of removing one of those variables from the Swiss Cheese model by say; just publishing the SID as we use in day-to-day operations (and have been for the last 20 years and will continue to use).
Tower Controller reported a departure turned earlier than expected to the heading into confliction with the previous departure.