Narrative:

Normal preflight start and taxi. No noted issues with the aircraft prior to takeoff. I was accomplishing the takeoff as the first officer. We were cleared for takeoff. Takeoff was normal until after the gear was up and we noticed a steady loud noise. Shortly after; we noticed a master caution light. The aircraft was not pressurizing and a forward cargo door light was illuminated. The captain coordinated with tower to return to the field. I continued to fly the aircraft for the approach and landing. No other issues were noted.

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Original NASA ASRS Text

Title: B737-300 First Officer experiences a loud steady noise shortly after takeoff and a Master Caution for Forward Cargo Door light and the aircraft will not pressurize.

Narrative: Normal preflight start and taxi. No noted issues with the aircraft prior to takeoff. I was accomplishing the takeoff as the F/O. We were cleared for takeoff. Takeoff was normal until after the gear was up and we noticed a steady loud noise. Shortly after; we noticed a Master Caution light. The aircraft was not pressurizing and a Forward Cargo door light was illuminated. The Captain coordinated with Tower to return to the field. I continued to fly the aircraft for the approach and landing. No other issues were noted.

Data retrieved from NASA's ASRS site as of July 2013 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.