Small aircraft pilot in turbulence penetrates floor of TCA.

Attributes
ACN	155025
Time
Date	199008
Day	Sat
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : sea
State Reference	WA
Altitude	msl bound lower : 2500 msl bound upper : 3300
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : sea
Operator	general aviation : personal
Make Model Name	Small Aircraft, High Wing, 1 Eng, Fixed Gear
Flight Phase	cruise other
Flight Plan	None
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : private
Experience	flight time last 90 days : 120 flight time total : 290 flight time type : 120
ASRS Report	155025
Events
Anomaly	non adherence : far other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : returned to intended course or assigned course
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

While flying from kelso, wa, to everett, wa, (paine field) I was flying a leg that was essentially direct from a point 5 NM north of olympia, wa, to paine field. This area lies beneath the 6000' MSL floor of the seattle TCA. Winds, as reported by the seattle ATIS, were from 250 degree. Substantial vertical air movement was occurring below a scattered layer of well developed cumulus clouds. After transitioning the olympia, wa, air traffic area, I allowed the aircraft to ride out the updrafts and downdrafts and my altitude was varying between approximately 2500'-3000' MSL. Being familiar with the area, I was navigating visly, while using LORAN to determine distance to paine field and to verify clearance from the tacoma-narrows air traffic area. When passing the area of vashon island (due west of seattle), I noticed I was east of my intended course and that I was very close to a segment of the TCA where the floor drops to 3000' sml. Although I was probably very near the segment boundary, I do not know with any certainty whether I had xed it or not. I believe that once I had established my course, (in fact, I could already see the boeing co buildings at paine) my attention to course deviation was diverted by the vertical excursions, and that even though I had known the wind direction, I had neglected to make the necessary course correction to maintain track.

Original NASA ASRS Text

Title: SMA PLT IN TURBULENCE PENETRATES FLOOR OF TCA.

Narrative: WHILE FLYING FROM KELSO, WA, TO EVERETT, WA, (PAINE FIELD) I WAS FLYING A LEG THAT WAS ESSENTIALLY DIRECT FROM A POINT 5 NM N OF OLYMPIA, WA, TO PAINE FIELD. THIS AREA LIES BENEATH THE 6000' MSL FLOOR OF THE SEATTLE TCA. WINDS, AS RPTED BY THE SEATTLE ATIS, WERE FROM 250 DEG. SUBSTANTIAL VERT AIR MOVEMENT WAS OCCURRING BELOW A SCATTERED LAYER OF WELL DEVELOPED CUMULUS CLOUDS. AFTER TRANSITIONING THE OLYMPIA, WA, ATA, I ALLOWED THE ACFT TO RIDE OUT THE UPDRAFTS AND DOWNDRAFTS AND MY ALT WAS VARYING BTWN APPROX 2500'-3000' MSL. BEING FAMILIAR WITH THE AREA, I WAS NAVIGATING VISLY, WHILE USING LORAN TO DETERMINE DISTANCE TO PAINE FIELD AND TO VERIFY CLRNC FROM THE TACOMA-NARROWS ATA. WHEN PASSING THE AREA OF VASHON ISLAND (DUE W OF SEATTLE), I NOTICED I WAS E OF MY INTENDED COURSE AND THAT I WAS VERY CLOSE TO A SEGMENT OF THE TCA WHERE THE FLOOR DROPS TO 3000' SML. ALTHOUGH I WAS PROBABLY VERY NEAR THE SEGMENT BOUNDARY, I DO NOT KNOW WITH ANY CERTAINTY WHETHER I HAD XED IT OR NOT. I BELIEVE THAT ONCE I HAD ESTABLISHED MY COURSE, (IN FACT, I COULD ALREADY SEE THE BOEING CO BUILDINGS AT PAINE) MY ATTN TO COURSE DEV WAS DIVERTED BY THE VERT EXCURSIONS, AND THAT EVEN THOUGH I HAD KNOWN THE WIND DIRECTION, I HAD NEGLECTED TO MAKE THE NECESSARY COURSE CORRECTION TO MAINTAIN TRACK.

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.