B737-700 crew had a track deviation in bos class B airspace.

Attributes
ACN	512450
Time
Date	200105
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	intersection : wylyy
State Reference	MA
Altitude	msl single value : 5000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	B737-700
Flight Phase	climbout : initial climbout : intermediate altitude
Route In Use	departure sid : wylyy
Flight Plan	IFR
Aircraft 2
Controlling Facilities	tracon : a90.tracon
Operator	common carrier : air carrier
Make Model Name	B727 Undifferentiated or Other Model
Flight Phase	climbout : initial climbout : intermediate altitude
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : cfi pilot : atp pilot : commercial
Experience	flight time last 90 days : 200 flight time total : 12000 flight time type : 7200
ASRS Report	512450
Events
Anomaly	conflict : airborne less severe non adherence : published procedure non adherence : far non adherence : company policies non adherence : clearance other anomaly other other spatial deviation
Resolutory Action	controller : issued alert
Miss Distance	horizontal : 12000 vertical : 1500
Supplementary
Problem Areas	ATC Human Performance Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

On bos departure, this crew received change in SID from the logan 2, to the wylyy 3 FMS-mht.' clearance change came just prior to being cleared into position on runway 27 at bos. First officer entered wylyy 3 in FMC/CDU and closed route discontinuity by putting mht immediately after wylyy intersection. SID calls for a 235 degree heading after wylyy to expect vectors on course. This crew allowed the aircraft to start a 90 degree right turn towards mht after wylyy rather than staying steady on a 235 degree heading. ATC called to ask our heading and assigned a 310 degree heading for traffic. An air carrier B727 was also climbing out after departing bos runway 33R. Our turn caused us to cross the flight path of the B727. Separation was never less than 1 mi (by TCASII display) and altitude never closer than 1500 ft (also by our TCASII display). No TCASII activation occurred. Our rate of climb was approximately 3500 FPM. A last min clearance change and failure of this crew to take the time to verify and brief the new SID were contributing factors here.

Original NASA ASRS Text

Title: B737-700 CREW HAD A TRACK DEV IN BOS CLASS B AIRSPACE.

Narrative: ON BOS DEP, THIS CREW RECEIVED CHANGE IN SID FROM THE LOGAN 2, TO THE WYLYY 3 FMS-MHT.' CLRNC CHANGE CAME JUST PRIOR TO BEING CLRED INTO POS ON RWY 27 AT BOS. FO ENTERED WYLYY 3 IN FMC/CDU AND CLOSED RTE DISCONTINUITY BY PUTTING MHT IMMEDIATELY AFTER WYLYY INTXN. SID CALLS FOR A 235 DEG HDG AFTER WYLYY TO EXPECT VECTORS ON COURSE. THIS CREW ALLOWED THE ACFT TO START A 90 DEG R TURN TOWARDS MHT AFTER WYLYY RATHER THAN STAYING STEADY ON A 235 DEG HDG. ATC CALLED TO ASK OUR HDG AND ASSIGNED A 310 DEG HDG FOR TFC. AN ACR B727 WAS ALSO CLBING OUT AFTER DEPARTING BOS RWY 33R. OUR TURN CAUSED US TO CROSS THE FLT PATH OF THE B727. SEPARATION WAS NEVER LESS THAN 1 MI (BY TCASII DISPLAY) AND ALT NEVER CLOSER THAN 1500 FT (ALSO BY OUR TCASII DISPLAY). NO TCASII ACTIVATION OCCURRED. OUR RATE OF CLB WAS APPROX 3500 FPM. A LAST MIN CLRNC CHANGE AND FAILURE OF THIS CREW TO TAKE THE TIME TO VERIFY AND BRIEF THE NEW SID WERE CONTRIBUTING FACTORS HERE.

Data retrieved from NASA's ASRS site as of July 2007 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.