Patent GB-565632-A (GB)
Title: Improvements in or relating to cockpit hoods
IPC: B64C1/14
Filed: 1943-01-16
Abstract: 565,632. Aircraft cockpit hoods. BOOTH, J. H. Jan. 16, 1943, No. 830. [Class 4] A cockpit hood of the kind described in Specification 562,808 has means for sealing and unsealing the hood and for jettisoning it, operated by two sets of slidable members operated by separate levers, each set of slidable members at the two sides of the cockpit being mechanically connected together across the cockpit at or near one end so as to be movable simultaneously. The sides of the hood have rollers 186, 187 running upon the upper and lower edges of rails 185, Fig. 7, the rails being mounted upon eccentrics 184 carried by sleeves secured by bolts 190 to levers 180 trunnioned within semicircular recesses in brackets 174, 175, Figs. 1 and 8, on the cockpit frame. The levers 180 are normally retained in the recesses in the brackets 174, 175 by projections 182, engaging beneath the upper parts of the brackets, and by bolts 207, 208 connected to a cable 200 secured to a hand lever 205. The other end of the cable passes around pulleys 202 on the brackets 174 to pass across the cockpit where it is connected to bolts for securing the levers 180 on the other side. By moving the lever 205 clockwise all the bolts are simultaneously removed and the levers 180 can then pivot about,the axes of the bolts 190 until they are free of the brackets 174, 175 so that the rails 185, and with them the hood, can be jettisoned. The sleeves carrying the eccentrics are provided with pinions 216 which engage with racks 217 connected by rods 218, additional teeth 222 on the undersides of the rear racks engaging pinions 223 on a crossshaft 224 so that both racks move simultaneously. The rack on one side of the cockpit is moved by a pinion 227, Fig. 1, on a shaft 226 connected to a hand lever 225 which has a locking-pin engageable with either of two holes 236 at the ends of a groove 237 in one of the brackets 175. By moving the lever 225, the edges of the cockpit cover can be moved into and out of sealing relation with a sealing strip 173 extending all round the cockpit opening. When the hood is raised to clear the sealing strip it can be slid backwards on the rails 185 and locked in various positions by bolts 177 engaging holes 214, Fig. 8, in angle strips secured to the brackets 174, 175. When the hood is completely closed the bolts 177 engage projections 176 on the forward brackets 175. The lever 205 is connected by a link 212 to a lever 209 on a shaft extending to the outside of the cockpit to enable the hood to be released from the outside. In alternative constructions, crank arms replace the eccentrics 184, and a system of links connects the two rack bars together. The rear end of the hood structure has a bracket 241, Fig. 7, within flanges of which is mounted a channel member 240 carrying rollers 238, 239. When the hood is raised to unseal it the rollers 238, 239 are in a position to engage a fixed rail 242 should the hood be slid backwards, and if the hood is jettisoned while in this position, the channel member 240 becomes detached from the bracket 241 by being twisted out of engagement with the flanges on the bracket.