When he was distracted during the preflight; the first officer of a lear 35 failed to secure all cow...

Narrative:

After takeoff we noticed that there continued to be a sign of airframe vibration. We rechecked the flaps and gear to make sure that they were in fact in the stowed position. Both verified to be stowed. While trying to figure out what else it may be the first officer remembered that he may have forgotten to latch the right hand engine cowl after checking the oil. An in flight visual inspection by the medical crew determined that the cowl was in fact open. We landed at the nearest airport. The after landing inspection showed that all three latches on the inboard side of the engine cowl and only the rear of three latches on the outboard side of the cowl were holding the cowl together. In our preflight duties I file the flight plans; do weight and balance; file the customs paperwork; while the first officer tows the aircraft to the fuel farm and transfers fuel and does the preflight inspection. When I am done with paperwork I come help fuel the aircraft. In our post flight brief it was determined that the first officer was checking the oil during the preflight. He stated that he was distracted by me when I showed up at the airplane. When I arrived at the aircraft he was on the other side of the aircraft doing the preflight inspection. I asked if he was ready for my help fueling. He stated that his thought was to answer me and come back to latch the cowl later. We fueled the airplane and towed it back to the hangar for our departure. This situation may have been avoided if I had done a follow up inspection. In the future it would a good idea to have two people do the preflight inspection to try and catch anything that may have been missed.

Original NASA ASRS Text

Title: When he was distracted during the preflight; the First Officer of a Lear 35 failed to secure all cowling fasteners on the right engine. Flight diverted to the nearest airport to properly secure the cowling.

Narrative: After takeoff we noticed that there continued to be a sign of airframe vibration. We rechecked the flaps and gear to make sure that they were in fact in the stowed position. Both verified to be stowed. While trying to figure out what else it may be the First Officer remembered that he may have forgotten to latch the right hand engine cowl after checking the oil. An in flight visual inspection by the medical crew determined that the cowl was in fact open. We landed at the nearest airport. The after landing inspection showed that all three latches on the inboard side of the engine cowl and only the rear of three latches on the outboard side of the cowl were holding the cowl together. In our preflight duties I file the flight plans; do weight and balance; file the customs paperwork; while the First Officer tows the aircraft to the fuel farm and transfers fuel and does the preflight inspection. When I am done with paperwork I come help fuel the aircraft. In our post flight brief it was determined that the First Officer was checking the oil during the preflight. He stated that he was distracted by me when I showed up at the airplane. When I arrived at the aircraft he was on the other side of the aircraft doing the preflight inspection. I asked if he was ready for my help fueling. He stated that his thought was to answer me and come back to latch the cowl later. We fueled the airplane and towed it back to the hangar for our departure. This situation may have been avoided if I had done a follow up inspection. In the future it would a good idea to have two people do the preflight inspection to try and catch anything that may have been missed.

Data retrieved from NASA's ASRS site as of April 2012 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.

Attributes
ACN	844697
Time
Date	200907
Local Time Of Day	0001-0600
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Dawn
Aircraft 1
Make Model Name	Learjet 35
Operating Under FAR Part	Part 135
Flight Phase	Climb
Route In Use	Vectors
Flight Plan	IFR
Component
Aircraft Component	Pylon Fasteners & Latches
Person 1
Function	Pilot Not Flying Captain
Qualification	Flight Crew Multiengine Flight Crew Instrument Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 110 Flight Crew Total 8100 Flight Crew Type 600
Events
Anomaly	Aircraft Equipment Problem Critical Deviation - Procedural Published Material / Policy

When he was distracted during the preflight; the first officer of a lear 35 failed to secure all cowling fasteners on the right engine. Flight diverted to the nearest airport to properly secure the cowling.