Air taxi flight crew has insufficient rest period.

Attributes
ACN	193826
Time
Date	199111
Day	Fri
Local Time Of Day	0001 To 0600
Place
Locale Reference	airport : lrd
State Reference	TX
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	Mixed
Light	Night
Aircraft 1
Controlling Facilities	artcc : zhu tower : ont
Operator	common carrier : air taxi
Make Model Name	Light Transport, Low Wing, 2 Turbojet Eng
Flight Phase	ground : preflight
Flight Plan	IFR
Person 1
Affiliation	company : air taxi
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 300 flight time total : 11000 flight time type : 3300
ASRS Report	193826
Person 2
Affiliation	company : air taxi
Function	flight crew : first officer
Qualification	pilot : atp
Events
Anomaly	non adherence : far other anomaly other
Independent Detector	other flight crewa
Resolutory Action	none taken : detected after the fact
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Departed on flight under rules of far 135 with inadequate rest period to meet far 135 requirements. The previous flight had 7 legs, 2 separate aircraft, and a total of 10.7 block-to-block flight hours. Required subsequent rest period, under far 135, is 12 hours. Without realizing that 10 block hours had been exceeded on the previous flight, I departed on a subsequent flight with only 10 hours and 30 mins of a rest period (11/xx/91). Although it was my responsibility to determine the required rest period, I failed to do so. My assumption was that 10 hours of flight time had not been exceeded on the previous flight. Because we changed aircraft before the trip was completed, I did not see a total flight time on the paperwork (logbook), exceeding 10 hours. I failed to add the 2 flight's block times together. Greater care on my part is the solution to avoiding a recurrence. In spite of the technical rule violation, I was well rested on the flight after the 10.5 hour rest.

Original NASA ASRS Text

Title: AIR TAXI FLC HAS INSUFFICIENT REST PERIOD.

Narrative: DEPARTED ON FLT UNDER RULES OF FAR 135 WITH INADEQUATE REST PERIOD TO MEET FAR 135 REQUIREMENTS. THE PREVIOUS FLT HAD 7 LEGS, 2 SEPARATE ACFT, AND A TOTAL OF 10.7 BLOCK-TO-BLOCK FLT HRS. REQUIRED SUBSEQUENT REST PERIOD, UNDER FAR 135, IS 12 HRS. WITHOUT REALIZING THAT 10 BLOCK HRS HAD BEEN EXCEEDED ON THE PREVIOUS FLT, I DEPARTED ON A SUBSEQUENT FLT WITH ONLY 10 HRS AND 30 MINS OF A REST PERIOD (11/XX/91). ALTHOUGH IT WAS MY RESPONSIBILITY TO DETERMINE THE REQUIRED REST PERIOD, I FAILED TO DO SO. MY ASSUMPTION WAS THAT 10 HRS OF FLT TIME HAD NOT BEEN EXCEEDED ON THE PREVIOUS FLT. BECAUSE WE CHANGED ACFT BEFORE THE TRIP WAS COMPLETED, I DID NOT SEE A TOTAL FLT TIME ON THE PAPERWORK (LOGBOOK), EXCEEDING 10 HRS. I FAILED TO ADD THE 2 FLT'S BLOCK TIMES TOGETHER. GREATER CARE ON MY PART IS THE SOLUTION TO AVOIDING A RECURRENCE. IN SPITE OF THE TECHNICAL RULE VIOLATION, I WAS WELL RESTED ON THE FLT AFTER THE 10.5 HR REST.

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.