Re: Does the Canadair RJ have thrust reversers?

Date:         08 Feb 99 02:49:18 
From: (Brian Clouse)
Organization: Prodigy Services Company  1-800-PRODIGY
References:   1
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The RJ most certainly does have reversers, of the cascade variety typical
of high-bypass turbofan installations.  On the 50-seat model now in
service, with the GE CF34-3A1 engines, actuation takes the form of the
aft part of the outer cowl translating aft, with the cascades (resembling
venetian blinds) translating with it.  Simultaneously, a set of blocker
doors pivots down from the outer flowpath of the fan cowl, blocking most
of the fan duct.  Fan discharge air hits the blocker doors and passes
through the cascades, exiting at a forward-and-outward angle which
provides reverse thrust.

Since the core still produces forward thrust, there is a lot of leakage,
and the fan air doesn't go directly forward, reverse thrust is only about
40% of takeoff thrust, but that still does the trick.  At some airports
(i.e. where the window glass is strong enough to take a flying pebble),
RJ pilots even use reverse thrust to back away from the gate.

The 70-seat version entering service next year, with the new CF34-8C1
engines, will have a new and much simpler nacelle design with fixed
cascades and no blocker doors.  Instead, the translating cowl will have
turning chutes integral with its structure, and will translate far enough
that the chutes will block most of the fan duct.  The core cowl will have
a much greater slope outward than on the current engine, so no blocker
doors are required.

Brian Clouse