An air carrier first officer reported an unexplained thirty minute delay arriving into phl on the vc...

Narrative:

While on the VCN8 arrival into phl we were given a 180 heading off the arrival for spacing. I was becoming obvious from the ATC communications that phl experiencing some sort of delays but we were not told what. ATC then gave us a 'present position hold'. We advised that we were unable when on a heading due to the automation (must be in navigation and on a route). ATC then instructed us to 'just fly a pattern' so we fly a race track pattern and timed it for 1 1/2 minutes. ATC was giving numerous aircraft this same clearance and I heard at least 2 that stated they were unable for the same reasons we stated (automation). After about 30 minutes we were then cleared to continue to phl via radar vectors. We were given numerous vectors on downwind and across final all while we had a visual on the airport. At this point we were down to about 5;000 pounds of fuel and were starting to mentally prepare for a diversion. We were finally cleared for the ILS 09R while configuring for the approach at approximately 3;000 ft we encountered a loss of 30-40 KTS of airspeed. We recovered and were back to a normal profile almost before we could react. I knew immediately we had encountered a windshear. Final was clear; and there were no windshear advisories; so we continued the approach and landed without incident with 4;500 pounds of fuel remaining. When we were on the ground; I gave a PIREP to the local controller and subsequently I heard 2 or 3 aircraft confirm my observations. The concern I have is that there was no indication to us of why we were delayed on our arrival and no indication of possible severe weather. Clearly there was some weather/convective activity at phl and in all probability was the cause of the delays. We had no indication of possible windshear on the airport. As an instructor pilot; I was very familiar with the aircraft's speed error tape and acceleration cue as it pertains to early detection of windshear. This allowed me to immediately advise the captain but we were out of it very quickly. Additionally; being aware of a low fuel state puts undue pressure for plan continuation bias. My concern with this incident is ATC's handling of the hold clearance and not warning all aircraft of potential hazardous weather; and the issuance of non standard holding clearances.

Original NASA ASRS Text

Title: An Air Carrier First Officer reported an unexplained thirty minute delay arriving into PHL on the VCN 8 Arrival to Runway 9. After being cleared for the approach the aircraft encountered an unannounced windshear of 30-40 KTS.

Narrative: While on the VCN8 arrival into PHL we were given a 180 heading off the arrival for spacing. I was becoming obvious from the ATC communications that PHL experiencing some sort of delays but we were not told what. ATC then gave us a 'present position hold'. We advised that we were unable when on a heading due to the automation (must be in NAV and on a route). ATC then instructed us to 'just fly a pattern' so we fly a race track pattern and timed it for 1 1/2 minutes. ATC was giving numerous aircraft this same clearance and I heard at least 2 that stated they were unable for the same reasons we stated (automation). After about 30 minutes we were then cleared to continue to PHL via radar vectors. We were given numerous vectors on downwind and across final all while we had a visual on the airport. At this point we were down to about 5;000 LBS of fuel and were starting to mentally prepare for a diversion. We were finally cleared for the ILS 09R while configuring for the approach at approximately 3;000 FT we encountered a loss of 30-40 KTS of airspeed. We recovered and were back to a normal profile almost before we could react. I knew immediately we had encountered a windshear. Final was clear; and there were no windshear advisories; so we continued the approach and landed without incident with 4;500 LBS of fuel remaining. When we were on the ground; I gave a PIREP to the Local Controller and subsequently I heard 2 or 3 aircraft confirm my observations. The concern I have is that there was no indication to us of why we were delayed on our arrival and no indication of possible severe weather. Clearly there was some weather/convective activity at PHL and in all probability was the cause of the delays. We had no indication of possible windshear on the airport. As an instructor pilot; I was very familiar with the aircraft's Speed Error Tape and Acceleration Cue as it pertains to early detection of Windshear. This allowed me to immediately advise the Captain but we were out of it very quickly. Additionally; being aware of a low fuel state puts undue pressure for Plan Continuation Bias. My concern with this incident is ATC's handling of the hold clearance and not warning all aircraft of potential hazardous weather; and the issuance of non standard holding clearances.

Data retrieved from NASA's ASRS site as of April 2012 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.

Attributes
ACN	884166
Time
Date	201004
Local Time Of Day	1801-2400
Place
Locale Reference	PHL.Airport
State Reference	PA
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Medium Transport Low Wing 2 Turbojet Eng
Operating Under FAR Part	Part 121
Flight Phase	Initial Approach
Flight Plan	IFR
Person 1
Function	Pilot Not Flying First Officer
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	ATC Issue All Types Deviation - Speed All Types Inflight Event / Encounter Weather / Turbulence Inflight Event / Encounter Fuel Issue

An air carrier first officer reported an unexplained thirty minute delay arriving into phl on the vcn 8 arrival to runway 9. After being cleared for the approach the aircraft encountered an unannounced windshear of 30-40 KTS.