National Airlines Flight 193

National Airlines Flight 193, registration N4744, Donna, was a Boeing 727-235 en route from Miami, Florida to Pensacola on May 8, 1978. It was scheduled with stops at Melbourne, Florida; Tampa; New Orleans, Louisiana and Mobile, Alabama. The accident occurred at night in low visibility from fog. During the descent into Pensacola Regional Airport it impacted Escambia Bay, sinking in 12 feet of water.
The instrument landing system for runway 16 had been out of service since January of that year for runway reconstruction. A non-precision approach to runway 25 was available instead. Prior to initiating the approach a twin engine Beechcraft reported breaking out of the overcast at 450 feet . The minimum descent altitude for this approach was 480 feet . This concerned the first officer who informed the captain in his opinion that plane had made an illegal approach. An Eastern Air Lines jet ahead of them reported briefly having the runway in sight before losing it in the clouds and going around.

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