A BE65 pilot flying a transition leg to an approach course descends without authority/authorized whe...

Attributes
ACN	391766
Time
Date	199801
Day	Sat
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : pye airport : sts
State Reference	CA
Altitude	msl bound lower : 3200 msl bound upper : 4000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zoa tower : pao
Operator	general aviation : personal
Make Model Name	Baron 55/Cochise
Operating Under FAR Part	Part 91
Flight Phase	descent other
Route In Use	arrival other
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : instrument pilot : commercial
Experience	flight time last 90 days : 42 flight time total : 946 flight time type : 156
ASRS Report	391766
Person 2
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Events
Anomaly	altitude deviation : excursion from assigned altitude non adherence : far non adherence : clearance other anomaly other
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance other
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

I was making several practice IFR approachs to maintain currency and proficiency. I had just finished the first at petaluma and was on the missed approach which heads you out to the point reyes VOR (pye) at 4000 ft MSL. While inbound to pye at 4000 ft in VMC, I picked my next IFR clearance which I had filed as follows: 'pye direct coati' which is the IAF into santa rosa on the ILS. The clearance I received was 'cleared to santa rosa via the point reyes transition, maintain 4000 ft.' since I was already at 4000 ft, all I had to do was continue inbound to point reyes VOR and then turn around and fly the point reyes transition. I have flown the ILS runway 32 into santa rosa probably 20 times over the last 4 yrs, starting at both the skaggs island VOR (sgd) and the pye VOR. When they have not wanted me to descend, the clearance has always been 'fly the 008 degree radial (from pye) direct coati, maintain 4000 ft' or it has been (from skaggs island VOR) 'fly 283 degree radial, direct coati, maintain 4000 ft.' this time the clearance was to 'fly the point reyes transition.' well, the only place you will find that transition is on the approach plate for the ILS runway 32. You won't find it on an en route chart. On the approach plate, it shows that the point reyes transition is to be flown at 3000 ft with no procedure turn so that is what I did. Upon leaving pye, I radioed to ZOA, 'baron XXXX leaving 4000 ft for 3000 ft per the published transition route.' when no one answered, I repeated the transmission. When no one answered (and there was no other conversation on frequency so I knew I hadn't interrupted anything) I started down for 3000 ft. Upon reaching about 3200 ft MSL, the controller radioed, 'baron XXXX what are you doing? I gave you 4000 ft.' I replied that I was following the transition route as published and had even radioed to tell him so. He said I was wrong to do so. I volunteered to go back to 4000 ft or any altitude he wanted me at. Instead, he cleared me for the approach from my current altitude and I went on my way. I descended into IMC and finished the approach.

Original NASA ASRS Text

Title: A BE65 PLT FLYING A TRANSITION LEG TO AN APCH COURSE DSNDS WITHOUT AUTH WHEN THE PLT INTERPS HIS TRANSITION RTE CLRNC AS A DSCNT CLRNC.

Narrative: I WAS MAKING SEVERAL PRACTICE IFR APCHS TO MAINTAIN CURRENCY AND PROFICIENCY. I HAD JUST FINISHED THE FIRST AT PETALUMA AND WAS ON THE MISSED APCH WHICH HEADS YOU OUT TO THE POINT REYES VOR (PYE) AT 4000 FT MSL. WHILE INBOUND TO PYE AT 4000 FT IN VMC, I PICKED MY NEXT IFR CLRNC WHICH I HAD FILED AS FOLLOWS: 'PYE DIRECT COATI' WHICH IS THE IAF INTO SANTA ROSA ON THE ILS. THE CLRNC I RECEIVED WAS 'CLRED TO SANTA ROSA VIA THE POINT REYES TRANSITION, MAINTAIN 4000 FT.' SINCE I WAS ALREADY AT 4000 FT, ALL I HAD TO DO WAS CONTINUE INBOUND TO POINT REYES VOR AND THEN TURN AROUND AND FLY THE POINT REYES TRANSITION. I HAVE FLOWN THE ILS RWY 32 INTO SANTA ROSA PROBABLY 20 TIMES OVER THE LAST 4 YRS, STARTING AT BOTH THE SKAGGS ISLAND VOR (SGD) AND THE PYE VOR. WHEN THEY HAVE NOT WANTED ME TO DSND, THE CLRNC HAS ALWAYS BEEN 'FLY THE 008 DEG RADIAL (FROM PYE) DIRECT COATI, MAINTAIN 4000 FT' OR IT HAS BEEN (FROM SKAGGS ISLAND VOR) 'FLY 283 DEG RADIAL, DIRECT COATI, MAINTAIN 4000 FT.' THIS TIME THE CLRNC WAS TO 'FLY THE POINT REYES TRANSITION.' WELL, THE ONLY PLACE YOU WILL FIND THAT TRANSITION IS ON THE APCH PLATE FOR THE ILS RWY 32. YOU WON'T FIND IT ON AN ENRTE CHART. ON THE APCH PLATE, IT SHOWS THAT THE POINT REYES TRANSITION IS TO BE FLOWN AT 3000 FT WITH NO PROC TURN SO THAT IS WHAT I DID. UPON LEAVING PYE, I RADIOED TO ZOA, 'BARON XXXX LEAVING 4000 FT FOR 3000 FT PER THE PUBLISHED TRANSITION RTE.' WHEN NO ONE ANSWERED, I REPEATED THE XMISSION. WHEN NO ONE ANSWERED (AND THERE WAS NO OTHER CONVERSATION ON FREQ SO I KNEW I HADN'T INTERRUPTED ANYTHING) I STARTED DOWN FOR 3000 FT. UPON REACHING ABOUT 3200 FT MSL, THE CTLR RADIOED, 'BARON XXXX WHAT ARE YOU DOING? I GAVE YOU 4000 FT.' I REPLIED THAT I WAS FOLLOWING THE TRANSITION RTE AS PUBLISHED AND HAD EVEN RADIOED TO TELL HIM SO. HE SAID I WAS WRONG TO DO SO. I VOLUNTEERED TO GO BACK TO 4000 FT OR ANY ALT HE WANTED ME AT. INSTEAD, HE CLRED ME FOR THE APCH FROM MY CURRENT ALT AND I WENT ON MY WAY. I DSNDED INTO IMC AND FINISHED THE 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 BE65 pilot flying a transition leg to an approach course descends without authority/authorized when the pilot interps his transition route clearance as a descent clearance.