Narrative:

While banking into 360 degree turn (left bank) canopy slid open, and popped out of its track, causing severe buffeting and loss of altitude. Retarded throttle to 2100 rpms, to maintain 1200 ft altitude, kept airspeed at 95 mph, slow flight (MCA). There was an extreme amount of drag with canopy popped out. It acted like a huge air brake. It disrupted air flow over rudder and elevator. I called pou tower on 124.00 and declared an emergency. I was concerned that when I lowered my landing gear, that my aircraft might stall out close to the ground. I advised pou of this. Pou acknowledged. I proceeded to land at pou, lowering my gear just short of touchdown. Landed without incident and taxied off runway 24. Callback conversation with reporter revealed the following information: the aircraft was a globe swift 125 model built in 1946. The canopy is plexiglass and has the ability to swing open from either side, for pilot or passenger entry. The reporter had been at 5000 ft doing 'lazy eights' and was just at the apex of the maneuver, turning left and down when the canopy 'vibrated and then opened.' the rest of the story was repeated as in the original text. Post flight inspection revealed that the plastic had worn into the metal slides and had come loose from the slide on one side. The 'fix' was to replace the plastic for a tighter seal. The reporter also places a locking pin in the canopy during any acrobatic maneuvers. Reporter called the FAA regarding this incident. They thought at first that the canopy was a mod to the original, not being very familiar with the history of this aircraft.

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Original NASA ASRS Text

Title: PVT PLT HAS CANOPY COME OFF THE TRACK IN HIS GLOBE SWIFT 125, EMER DECLARED LNDG.

Narrative: WHILE BANKING INTO 360 DEG TURN (L BANK) CANOPY SLID OPEN, AND POPPED OUT OF ITS TRACK, CAUSING SEVERE BUFFETING AND LOSS OF ALT. RETARDED THROTTLE TO 2100 RPMS, TO MAINTAIN 1200 FT ALT, KEPT AIRSPD AT 95 MPH, SLOW FLT (MCA). THERE WAS AN EXTREME AMOUNT OF DRAG WITH CANOPY POPPED OUT. IT ACTED LIKE A HUGE AIR BRAKE. IT DISRUPTED AIR FLOW OVER RUDDER AND ELEVATOR. I CALLED POU TWR ON 124.00 AND DECLARED AN EMER. I WAS CONCERNED THAT WHEN I LOWERED MY LNDG GEAR, THAT MY ACFT MIGHT STALL OUT CLOSE TO THE GND. I ADVISED POU OF THIS. POU ACKNOWLEDGED. I PROCEEDED TO LAND AT POU, LOWERING MY GEAR JUST SHORT OF TOUCHDOWN. LANDED WITHOUT INCIDENT AND TAXIED OFF RWY 24. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE ACFT WAS A GLOBE SWIFT 125 MODEL BUILT IN 1946. THE CANOPY IS PLEXIGLASS AND HAS THE ABILITY TO SWING OPEN FROM EITHER SIDE, FOR PLT OR PAX ENTRY. THE RPTR HAD BEEN AT 5000 FT DOING 'LAZY EIGHTS' AND WAS JUST AT THE APEX OF THE MANEUVER, TURNING L AND DOWN WHEN THE CANOPY 'VIBRATED AND THEN OPENED.' THE REST OF THE STORY WAS REPEATED AS IN THE ORIGINAL TEXT. POST FLT INSPECTION REVEALED THAT THE PLASTIC HAD WORN INTO THE METAL SLIDES AND HAD COME LOOSE FROM THE SLIDE ON ONE SIDE. THE 'FIX' WAS TO REPLACE THE PLASTIC FOR A TIGHTER SEAL. THE RPTR ALSO PLACES A LOCKING PIN IN THE CANOPY DURING ANY ACROBATIC MANEUVERS. RPTR CALLED THE FAA REGARDING THIS INCIDENT. THEY THOUGHT AT FIRST THAT THE CANOPY WAS A MOD TO THE ORIGINAL, NOT BEING VERY FAMILIAR WITH THE HISTORY OF THIS ACFT.

Data retrieved from NASA's ASRS site as of July 2007 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.