AN ACR MLG FAILED TO FOLLOW THE SID PROCS AT HPN.

Narrative

THE EXTENDED CTRLINE OF RWY 16 AT WHITE PLAINS; NY (HPN) INTERSECTS THE APCH COURSE TO LGA RWY 22 APPROX 5 MI (OR MORE) FROM THE DEP END OF HPN RWY 16. THAT'S A DANGEROUS CONDITION! THE ONLY THING PREVENTING A DEADLY TFC CONFLICT IS THE REQUIREMENT FOR A R TURN TO THE NW AT 800 FT MSL DEPARTING HPN RWY 16 AS DEPICTED ON THE SID FOR WHITE PLAINS. WHITE PLAINS CLRNC DELIVERY ISSUES THE SID AS PART OF THE CLRNC WITHOUT REF TO THE NEED FOR ANY TURNS. THIS WAS THE SECOND TIME THE FO AND I HAD OPERATED AT WHITE PLAINS. ON THIS DAY THE WX WAS 100 FT OVCST; 1/2 MI VISIBILITY FOG; LIGHT RAIN. HPN IS A HIGHLY CONGESTED ARPT REQUIRING A HIGH LEVEL OF VIGILANCE IN GND OPS DUE TO INADEQUATE RAMPS AND TXWYS. OUR LACK OF FAMILIARITY WITH THE APT WAS COMPLICATED BY THE HAZARDS ASSOCIATED WITH THE LOW VISIBILITY AND CEILING CONDITIONS AT THE ARPT. AS CAPT AND PF; I HAD DISCUSSED THE SID; BUT THE PLAN VIEW ON THE FOLD-OUT FLY LEAF WAS FOLDED UNDER TO FIT ON THE YOKE CLIPBOARD. THE DESCRIPTION OF THE TURN IS IN SMALL PRINT ON THE BOTTOM OF THE PAGE. NO REF TO TURNS AFTER TKOF ARE EVER MADE BY CLRNC DELIVERY; GND; OR TWR PERSONNEL. AFTER TKOF WE CONTINUED ON RWY HDG AND LEVELED OFF AT OUR CLRED ALT OF 2000 FT MSL (MISSING THE TURN AT 800 FT MSL). ON CONTACT WITH NY DEP WE WERE IMMEDIATELY DIRECTED TO TURN R TO THE SID HDG. WE WERE LUCKY THAT NO TFC CONFLICT RESULTED FROM OUR OVERSIGHT. WE COULD HAVE HIT SOMEONE! RECOMMENDATIONS: 1) KNOWN POTENTIAL TFC CONFLICTS WITH OTHER NEIGHBORING ARPT/AIRSPACE OPS BE NOTED AS 'CAUTIONS' ON ALL PUBLISHED SIDS; THEREBY EMPHASIZING THE IMPORTANCE OF CLOSE COMPLIANCE WITH SID PROCS. 2) ARPT TWR CTLRS SHOULD BE REQUIRED TO STIPULATE TURN HDGS AS PART OF TKOF CLRNC WHERE POTENTIAL TFC CONFLICTS EXIST. 3) TWR PERSONNEL SHOULD BE REMINDED OF IMPORTANCE OF CLOSELY MONITORING COMPLIANCE WITH SID AND TWR TURN INSTRUCTIONS; ESPECIALLY IN REDUCED VISIBILITY CONDITIONS. SUPPLEMENTAL INFO FROM ACN 25754: CREW INTERRUPTED SEVERAL TIMES DURING PRE TKOF BRIEFING (INCLUDING SID) BY FLT ATTENDANTS COMPLAINING OF PAX UNWILLING TO GIVE UP THEIR SEATS. WE MISREAD THE RWY 16 TURN TO 320 DEGS TO BE AT 1800 FT VERSUS 800 FT (SEE THE DEP SID -- THE AT OR BELOW LINE LOOKED TO BE A '1'). SUGGESTION TO PREVENT FUTURE OCCURRENCE: HAVE TWR PROVIDE THE INITIAL TURN HDG WITH TKOF CLRNC. WE WERE SIMPLY GIVEN 'CLRED FOR TKOF.'