Beechcraft 99 pilot reported taking off with the crew hatch not fully secured; and that the hatch su...

Attributes
ACN	1486266
Time
Date	201710
Local Time Of Day	1801-2400
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	Mixed
Light	Night
Aircraft 1
Make Model Name	Airliner 99
Operating Under FAR Part	Part 135
Flight Phase	Climb Initial Climb
Route In Use	Vectors
Flight Plan	IFR
Component
Aircraft Component	Service/Access Door
Person 1
Function	Single Pilot
Qualification	Flight Crew Commercial Flight Crew Flight Instructor Flight Crew Instrument Flight Crew Multiengine
Experience	Flight Crew Last 90 Days 85 Flight Crew Total 1376 Flight Crew Type 72
Events
Anomaly	Aircraft Equipment Problem Critical Deviation - Procedural Clearance Deviation - Track / Heading All Types

Narrative:

I departed [the airport] with the crew hatch not fully secured. Prior to takeoff; the latch appeared to be over the pin; but was apparently not fully seated. Shortly after takeoff; wind noise increased. After clearing IMC; an attempt was made to secure the hatch. The handle bolted to the hatch tore free from the hatch allowing it to fly open and off of the aircraft. The timing was also unfortunately after frequency change approval; but before initial contact [with] center.prior to requesting clearance to return to [departure airport]; a turn to the north and leveling at a lower altitude was accomplished to remain close to the airport. There were storms in the area; but the incident occurred in VMC. ATC allowed return to [departure airport] to inspect for damage; the subsequent approach and landing was uneventful; priority handling was not requested or granted. There was no damage to the empennage; or its control surfaces.I think I should have contacted ATC to obtain clearance prior to making the deviation. Had the distraction occurred in IMC; the priority of clearance and communication would have been higher and the deviation would not have occurred.

Original NASA ASRS Text

Title: Beechcraft 99 pilot reported taking off with the crew hatch not fully secured; and that the hatch subsequently departed that aircraft.

Narrative: I departed [the Airport] with the crew hatch not fully secured. Prior to takeoff; the latch appeared to be over the pin; but was apparently not fully seated. Shortly after takeoff; wind noise increased. After clearing IMC; an attempt was made to secure the hatch. The handle bolted to the hatch tore free from the hatch allowing it to fly open and off of the aircraft. The timing was also unfortunately after frequency change approval; but before initial contact [with] Center.Prior to requesting clearance to return to [departure airport]; a turn to the north and leveling at a lower altitude was accomplished to remain close to the airport. There were storms in the area; but the incident occurred in VMC. ATC allowed return to [departure airport] to inspect for damage; the subsequent approach and landing was uneventful; priority handling was not requested or granted. There was no damage to the empennage; or its control surfaces.I think I should have contacted ATC to obtain clearance prior to making the deviation. Had the distraction occurred in IMC; the priority of clearance and communication would have been higher and the deviation would not have occurred.

Data retrieved from NASA's ASRS site 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.