C560 crew had severe wake turbulence from a same direction, same altitude B737-800 in ZOA class a.

Attributes
ACN	612931
Time
Date	200403
Day	Tue
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : zoa.artcc navaid : fra.vortac
State Reference	CA
Altitude	msl single value : 37000
Environment
Flight Conditions	VMC
Weather Elements	Turbulence
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zoa.artcc
Operator	general aviation : corporate
Make Model Name	Citation III, VI, VII
Operating Under FAR Part	Part 91
Flight Phase	cruise : level
Flight Plan	IFR
Aircraft 2
Controlling Facilities	artcc : zoa.artcc
Operator	common carrier : air carrier
Make Model Name	B737-800
Operating Under FAR Part	Part 121
Flight Phase	cruise : level
Flight Plan	IFR
Person 1
Affiliation	company : corporate
Function	flight crew : captain oversight : pic
Qualification	pilot : multi engine pilot : cfi pilot : atp pilot : private
Experience	flight time last 90 days : 148 flight time total : 5100 flight time type : 1345
ASRS Report	612931
Person 2
Affiliation	company : corporate
Function	flight crew : first officer
Qualification	pilot : multi engine pilot : atp
Experience	flight time last 90 days : 60 flight time total : 4500 flight time type : 330
ASRS Report	613157
Events
Anomaly	altitude deviation : excursion from assigned altitude inflight encounter : wake turbulence other anomaly
Independent Detector	other flight crewa other flight crewb
Resolutory Action	controller : issued new clearance controller : separated traffic flight crew : exited adverse environment flight crew : regained aircraft control flight crew : took evasive action
Miss Distance	horizontal : 84000 vertical : 0
Supplementary
Problem Areas	Weather Environmental Factor
Primary Problem	Environmental Factor

Narrative:

After leveling off at FL370 on a smooth flight, our citation III was in cruise flight. The C650 was 14 NM behind a B737-800. ATC requested the B737 to increase speed. The B737 accepted .78 mach and our citation was requested to slow to .77 mach from .83 mach because the horizontal distance was decreasing. The B737 was at FL370 also. The citation encountered severe wake turbulence. The airplane rolled both left and right 45 degrees and pitched up 20 degrees. I turned off the autoplt and informed ATC that we were encountering severe wake turbulence. At that time, we further requested higher and FL390 -- wrong way. With our passenger's safety and concern, we climbed above and were assigned the altitude of FL390. Once at our new altitude, the flight was smooth and there were no other issues. Supplemental information from acn 613157: within approximately 1 min we experienced moderate to severe wake turbulence with our aircraft rolling +/-45 degrees left and right and pitching 20-30 degrees nose up. As the PIC regained control, we had gained approximately 800 ft. We requested a higher altitude.

Original NASA ASRS Text

Title: C560 CREW HAD SEVERE WAKE TURB FROM A SAME DIRECTION, SAME ALT B737-800 IN ZOA CLASS A.

Narrative: AFTER LEVELING OFF AT FL370 ON A SMOOTH FLT, OUR CITATION III WAS IN CRUISE FLT. THE C650 WAS 14 NM BEHIND A B737-800. ATC REQUESTED THE B737 TO INCREASE SPD. THE B737 ACCEPTED .78 MACH AND OUR CITATION WAS REQUESTED TO SLOW TO .77 MACH FROM .83 MACH BECAUSE THE HORIZ DISTANCE WAS DECREASING. THE B737 WAS AT FL370 ALSO. THE CITATION ENCOUNTERED SEVERE WAKE TURB. THE AIRPLANE ROLLED BOTH L AND R 45 DEGS AND PITCHED UP 20 DEGS. I TURNED OFF THE AUTOPLT AND INFORMED ATC THAT WE WERE ENCOUNTERING SEVERE WAKE TURB. AT THAT TIME, WE FURTHER REQUESTED HIGHER AND FL390 -- WRONG WAY. WITH OUR PAX'S SAFETY AND CONCERN, WE CLBED ABOVE AND WERE ASSIGNED THE ALT OF FL390. ONCE AT OUR NEW ALT, THE FLT WAS SMOOTH AND THERE WERE NO OTHER ISSUES. SUPPLEMENTAL INFO FROM ACN 613157: WITHIN APPROX 1 MIN WE EXPERIENCED MODERATE TO SEVERE WAKE TURB WITH OUR ACFT ROLLING +/-45 DEGS L AND R AND PITCHING 20-30 DEGS NOSE UP. AS THE PIC REGAINED CTL, WE HAD GAINED APPROX 800 FT. WE REQUESTED A HIGHER ALT.

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.