We got the F-5 not because it was dbl engined. More because the
first series was nearly free under FMS. The subsequent ones were
not free when the economy boomed and foriegn aid dwindled.
F-5 was dbl engined because costs. Excerpt from "Northrop F-5/F-20"
by Jerry Scutts, Modern Combat Aircraft.
"One drawback foreseen was the use of a large conventional
turbojet: not only would this require a large amount of fuel, but
its cost would be high. This factor was one of the primary reasons
for the cancellation of furthter work on the Fang. Tom Jones, then
Northrop Planning Officer (later President and Chief Executive)
felt that this was not the way the company should go. He pressed
for a reassessment of the fighter programme, with more emphasis on
keeping the cost down.
At this point, Northuop's brainchild was helped considerably by the
availability of very small turbojets being produced primarily for
guided missiles. With very high thrust to weight ratios and
dimension modest enough to fit into a very compact fighter
airframe, these engines became the crux of the aircraft Northrop
was plannning."
The F-5 has the smallest engines ever. The engines start after the
auxilary air intakes. Look at any F-5 taking off. It is that
small.
Due to same cost reasons, it have dry wings, eg all fuel is carried
in the main fuselage.
The end result, the smallest fighter supersonic aircraft that can
take off from a grass strip. You need to respect this little bird
as it is used for Agressor training. This is mainly dogfight
without radar using mainly eyes.
Cons, limited stores stations, limited radar capability.
