An airborne police helicopter crossed over a taxiing aircraft at a very low altitude after local ATC...

Attributes
ACN	804722
Time
Date	200809
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	agl single value : 100
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : zzz.tower
Operator	other
Make Model Name	Helicopter
Operating Under FAR Part	Part 91
Flight Phase	climbout : takeoff
Flight Plan	None
Aircraft 2
Controlling Facilities	tower : zzz.tower
Operator	common carrier : air carrier
Make Model Name	B737 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	ground : taxi
Flight Plan	IFR
Person 1
Affiliation	government other
Qualification	pilot : commercial pilot : instrument pilot : multi engine pilot : cfi
Experience	flight time last 90 days : 100 flight time total : 4240 flight time type : 2150
ASRS Report	804722
Person 2
Affiliation	government other
Events
Anomaly	conflict : airborne less severe non adherence : far other spatial deviation
Independent Detector	other flight crewa other flight crewb
Resolutory Action	none taken : detected after the fact
Miss Distance	horizontal : 200 vertical : 100
Supplementary
Problem Areas	ATC Human Performance Flight Crew Human Performance
Primary Problem	Ambiguous

Narrative:

I was flying in the police department's helicopter. Captain was given a takeoff clearance by the tower to proceed north between the runways and remain east of runway 35L. One airplane was on final approach to runway 35L; a second airplane was waiting on taxiway C at runway 35L; and a third airplane (B737) was taxiing sbound on taxiway C towards us as we took off. There was a space between the holding aircraft and the B737 and captain passed in front of the B737 as he departed. There were additional aircraft coming sbound on taxiway C that prevented him from moving further away from runway 35L. As we continued to climb we passed over an aircraft that had just turned off runway 35L onto taxiway T or G. At that point we were at least 400 ft AGL and climbing. It was captain's belief that the controller wanted him to take off behind the holding aircraft and avoid overflying the B737. The B737 appeared to slow down as it saw us departing. There was no comment from the tower or the B737 during the takeoff. As we approached taxiway T the controller asked us to hold; which put us over the taxiing aircraft. It is my belief that the tower should have held us until it was clear for a west departure or captain should have confirmed that he was cleared to depart over taxiway C. After the patrol flight was over we discussed the event and options that were available to us given the current wind conditions. Corrective action will be taken to avoid similar situation in the future.

Original NASA ASRS Text

Title: AN AIRBORNE POLICE HELI CROSSED OVER A TAXIING ACFT AT A VERY LOW ALT AFTER LCL ATC ASKED THAT THE HELI HOLD FOR DEP TFC.

Narrative: I WAS FLYING IN THE POLICE DEPT'S HELI. CAPT WAS GIVEN A TKOF CLRNC BY THE TWR TO PROCEED N BTWN THE RWYS AND REMAIN E OF RWY 35L. ONE AIRPLANE WAS ON FINAL APCH TO RWY 35L; A SECOND AIRPLANE WAS WAITING ON TXWY C AT RWY 35L; AND A THIRD AIRPLANE (B737) WAS TAXIING SBOUND ON TXWY C TOWARDS US AS WE TOOK OFF. THERE WAS A SPACE BTWN THE HOLDING ACFT AND THE B737 AND CAPT PASSED IN FRONT OF THE B737 AS HE DEPARTED. THERE WERE ADDITIONAL ACFT COMING SBOUND ON TXWY C THAT PREVENTED HIM FROM MOVING FURTHER AWAY FROM RWY 35L. AS WE CONTINUED TO CLB WE PASSED OVER AN ACFT THAT HAD JUST TURNED OFF RWY 35L ONTO TXWY T OR G. AT THAT POINT WE WERE AT LEAST 400 FT AGL AND CLBING. IT WAS CAPT'S BELIEF THAT THE CTLR WANTED HIM TO TAKE OFF BEHIND THE HOLDING ACFT AND AVOID OVERFLYING THE B737. THE B737 APPEARED TO SLOW DOWN AS IT SAW US DEPARTING. THERE WAS NO COMMENT FROM THE TWR OR THE B737 DURING THE TKOF. AS WE APCHED TXWY T THE CTLR ASKED US TO HOLD; WHICH PUT US OVER THE TAXIING ACFT. IT IS MY BELIEF THAT THE TWR SHOULD HAVE HELD US UNTIL IT WAS CLR FOR A W DEP OR CAPT SHOULD HAVE CONFIRMED THAT HE WAS CLRED TO DEPART OVER TXWY C. AFTER THE PATROL FLT WAS OVER WE DISCUSSED THE EVENT AND OPTIONS THAT WERE AVAILABLE TO US GIVEN THE CURRENT WIND CONDITIONS. CORRECTIVE ACTION WILL BE TAKEN TO AVOID SIMILAR SITUATION IN THE FUTURE.

Data retrieved from NASA's ASRS site as of May 2009 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.

An airborne police helicopter crossed over a taxiing aircraft at a very low altitude after local ATC asked that the helicopter hold for departure traffic.