Thunderjet Canopy Early


Thunderjets were equiped with a blown "bubble" canopy. The canopy on the "early" XP-84 through F-84D Thunderjets was not braced nor was it equiped with any access port to service the equipment housed under the aft portion of the canopy. This "early" canopy was also eight inches shorter than the canopy used on the "late" F-84E/G Thunderjets.

The unbraced canopies were suffered from breakage -- blowouts -- due to the aerodynamic forces imposed upon them. The "fix" was accomplished by the addition of white fiberglass bracing tapes bonded to the exterior of the canopy. This fix commenced with the G-models, and generally was retrofitted to active Thunderjets. During testing to determine the extent of bracing required, the initial fix consisted of one bracing tape, about two-inches wide, applied just above the back of the ejection seat. I don't yet have information as to the number (quantity) or (serial) numbers of the aircraft so equiped. In any case, the single bracing tape did not add sufficient strength to cure the problem, and the "birdcage" scheme was adopted.

Service personnel encountered access difficulties when called upon to service the equipment under the aft canopy. Their complaints lead to official requests to Republic to provide some manner of access to more easily service the equipment. Subsequently, an access port was installed in the right side of the aft canopy. This access port began to be added during production of the D-models, and well before the bracing tapes were retrofitted.

Because of the addition of the access port, the interim addition of the single bracing tape, the installation of bracing tapes starting with the G-models, and the retrofit of bracing tapes to the older Thunderjets, it is possible to see photos of canopies with a variety of appearances. These appearances could be any combination of short or long canopy, single or "birdcage" bracing tapes, and without or with the access port. Further, any of the models prior to the G-models could appear in one photograph with one version of canopy, and in a later photo with another of the versions. The chronological rule of thumb -- but not mandatory depending on field maintenance done -- would be from unbraced to braced canopy, and from without to with the access port. Then there are the anomalies to consider: for example, a front half of a short canopy patched to the aft half of a long canopy, such as was done on the F-84E at Planes of Fame in Chino. See the Canopy Comparison.

"The Canopy" on the Thunderjet appears to be pretty simple subject; however, like some other not-so-obvious progessions and changes, the progressions in canopy fitment to the Thunderjet from XP-84 to F-84G is more complex than it may first appear.

The illustration of the early Thunderjet canopy is from before bracing tapes and before the access port were added. The photos are of the F-84C at March Field Museum, and show the added bracing tapes and access port.

Illustration from the Republic archives courtesy of E.J. Boss. Photos by Bruce Craig.

F-84B canopy and controls F-84C canopy right side F-84C canopy left side

XP-84 through F-84D canopy and controls

Right side of F-84C canopy

Left side of F-84C canopy


Contents Copyright 1997-1999 Bruce Craig -- All Rights Reserved


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