A landing SF340 has to go around after experiencing a 30 degree roll on short final to runway 4L at ...

Attributes
ACN	413441
Time
Date	199809
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : bos
State Reference	MA
Altitude	agl bound lower : 100 agl bound upper : 1300
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : bos
Operator	common carrier : air carrier
Make Model Name	SF 340A
Operating Under FAR Part	Part 121
Navigation In Use	Other
Flight Phase	descent : approach landing : go around
Route In Use	approach : straight in arrival other
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	DC-10 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	Other
Flight Phase	descent : approach
Route In Use	approach : straight in arrival other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : cfi pilot : atp
Experience	flight time last 90 days : 240 flight time total : 7000 flight time type : 3500
ASRS Report	413441
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	inflight encounter other other anomaly other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : regained aircraft control flight crew : declared emergency flight crew : exited adverse environment other
Consequence	Other
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	other
Situations
ATC Facility	procedure or policy : unspecified
Airport	other physical facility

Narrative:

Lahso. While on approach to runway 4L at bos, it is not uncommon to be abeam or slightly behind to the left of a large or heavy aircraft. It is not uncommon for the prevailing winds to be out of the east, allowing wingtip vortices (wake turbulence) to drift into the runway 4L approach course. Tower assigns clearance 'XYZ123 you're cleared to land runway 4L hold short of runway 33R.' what makes this situation unsafe or a hazard is when local tower puts a large or heavy into position on runway 9 and is timing the runway 9 departure on the arrival of runway 4R. Typically, the runway 9 departure is sitting 'ready to go, power up' (more than idle). The thrust from the runway 9 departure along with the drifting wake from the arrival on runway 4R, and the clearance to lahso is not as safe an operation as this could be. Heavy aircraft range from B757, B747, airbus 330, DC10, B767, B777, L1011. What makes this very interesting is when the runway 9 departure is an L1011 or DC10, high tail mounted engine. No easy answer other than go around. Callback conversation with reporter revealed the following information: the captain said this was an SF340 and thought that this was the worst of all worlds for smaller landing aircraft. He wanted to know why ATC usually placed the heavier aircraft on the right runway. This sequence placed the smaller aircraft on the downwind side of the larger aircraft, experiencing their wake turbulence and also the jetblast from runway 9 traffic holding for an immediate takeoff after landing traffic runway 4R. The first officer was flying the aircraft but the captain took over and performed the go around. The tower does not issue advisories to aircraft landing runway 4L about the jetblast possibilities. The captain wasn't certain what he experienced, jetblast or wake turbulence. He felt it was a possible combination of both. He sent in a company report and one to his union safety committee. They said they would take this up with the tower. The lahso clearance seemed to be the lesser of the evils presented to him on that approach.

Original NASA ASRS Text

Title: A LNDG SF340 HAS TO GO AROUND AFTER EXPERIENCING A 30 DEG ROLL ON SHORT FINAL TO RWY 4L AT BOS. ALT WAS ABOUT 200- 300 FT AGL. FLT HAD BEEN GIVEN A LAHSO BUT HAD A DC10 ON FINAL TO RWY 4R AND A DC10 WITH PWR UP, HOLDING ON RWY 9 FOR AN IMMEDIATE DEP.

Narrative: LAHSO. WHILE ON APCH TO RWY 4L AT BOS, IT IS NOT UNCOMMON TO BE ABEAM OR SLIGHTLY BEHIND TO THE L OF A LARGE OR HVY ACFT. IT IS NOT UNCOMMON FOR THE PREVAILING WINDS TO BE OUT OF THE E, ALLOWING WINGTIP VORTICES (WAKE TURB) TO DRIFT INTO THE RWY 4L APCH COURSE. TWR ASSIGNS CLRNC 'XYZ123 YOU'RE CLRED TO LAND RWY 4L HOLD SHORT OF RWY 33R.' WHAT MAKES THIS SIT UNSAFE OR A HAZARD IS WHEN LCL TWR PUTS A LARGE OR HVY INTO POS ON RWY 9 AND IS TIMING THE RWY 9 DEP ON THE ARR OF RWY 4R. TYPICALLY, THE RWY 9 DEP IS SITTING 'READY TO GO, PWR UP' (MORE THAN IDLE). THE THRUST FROM THE RWY 9 DEP ALONG WITH THE DRIFTING WAKE FROM THE ARR ON RWY 4R, AND THE CLRNC TO LAHSO IS NOT AS SAFE AN OP AS THIS COULD BE. HVY ACFT RANGE FROM B757, B747, AIRBUS 330, DC10, B767, B777, L1011. WHAT MAKES THIS VERY INTERESTING IS WHEN THE RWY 9 DEP IS AN L1011 OR DC10, HIGH TAIL MOUNTED ENG. NO EASY ANSWER OTHER THAN GO AROUND. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE CAPT SAID THIS WAS AN SF340 AND THOUGHT THAT THIS WAS THE WORST OF ALL WORLDS FOR SMALLER LNDG ACFT. HE WANTED TO KNOW WHY ATC USUALLY PLACED THE HEAVIER ACFT ON THE R RWY. THIS SEQUENCE PLACED THE SMALLER ACFT ON THE DOWNWIND SIDE OF THE LARGER ACFT, EXPERIENCING THEIR WAKE TURB AND ALSO THE JETBLAST FROM RWY 9 TFC HOLDING FOR AN IMMEDIATE TKOF AFTER LNDG TFC RWY 4R. THE FO WAS FLYING THE ACFT BUT THE CAPT TOOK OVER AND PERFORMED THE GAR. THE TWR DOES NOT ISSUE ADVISORIES TO ACFT LNDG RWY 4L ABOUT THE JETBLAST POSSIBILITIES. THE CAPT WASN'T CERTAIN WHAT HE EXPERIENCED, JETBLAST OR WAKE TURB. HE FELT IT WAS A POSSIBLE COMBINATION OF BOTH. HE SENT IN A COMPANY RPT AND ONE TO HIS UNION SAFETY COMMITTEE. THEY SAID THEY WOULD TAKE THIS UP WITH THE TWR. THE LAHSO CLRNC SEEMED TO BE THE LESSER OF THE EVILS PRESENTED TO HIM ON THAT APCH.

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.

A landing SF340 has to go around after experiencing a 30 degree roll on short final to runway 4L at bos. Altitude was about 200- 300 ft AGL. Flight had been given a lahso but had a DC10 on final to runway 4R and a DC10 with power up, holding on runway 9 for an immediate departure.