Narrative:

After normal takeoff with first officer at controls and gear up call; we heard loud air noises and vibrations coming from the nose gear area. All gear indicated up and locked. After we attained a safe altitude; climbing and with the autopilot on; we put the gear lever down and still had 3 green lights. In accordance with the checklist; we brought the gear handle up. This time we had an unsafe nose indication (red light) with the continued loud air noise and vibration. Again the landing gear lever was selected down and a safe indication was reestablished. The loud air noise and vibration continued. When the weather radar stopped working with a large storm over ZZZ; we decided to divert. An emergency was declared. After a normal landing by the captain with emergency equipment on hand; it was determined that the nose gear door did not close. Just before we left; I was required to go outside to verify fuel load in our right main tank. We had a deferred problem with the right main quantity indicator. On the way; I noticed several individuals in the nosewheel well (gear doors open). One turned out to be the fuel truck operator and the other I thought was a maintenance representative. I verified the fuel quantity and hurried back to the cockpit because it had started to rain and we were at departure time. I did not notice if the gear doors were open nor did the ground crew during push back inform us of any abnormality.

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Original NASA ASRS Text

Title: A MD80 departed and the nose gear doors did not close giving an unsafe nose gear warning. The landing gear gave a safe indication when down. An emergency was declared followed by a landing at a diversionary airport.

Narrative: After normal takeoff with First Officer at controls and gear up call; we heard loud air noises and vibrations coming from the nose gear area. All gear indicated up and locked. After we attained a safe altitude; climbing and with the autopilot on; we put the gear lever down and still had 3 green lights. In accordance with the checklist; we brought the gear handle up. This time we had an unsafe nose indication (red light) with the continued loud air noise and vibration. Again the landing gear lever was selected down and a safe indication was reestablished. The loud air noise and vibration continued. When the weather radar stopped working with a large storm over ZZZ; we decided to divert. An emergency was declared. After a normal landing by the Captain with emergency equipment on hand; it was determined that the nose gear door did not close. Just before we left; I was required to go outside to verify fuel load in our right main tank. We had a deferred problem with the right main quantity indicator. On the way; I noticed several individuals in the nosewheel well (gear doors open). One turned out to be the fuel truck operator and the other I thought was a maintenance representative. I verified the fuel quantity and hurried back to the cockpit because it had started to rain and we were at departure time. I did not notice if the gear doors were open nor did the ground crew during push back inform us of any abnormality.

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.