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Hi Speeddemon651, here's my take.
The original multiple disc brakes installed on D-17 (most military thus the most prevalent type still flying) through the F-17 were very well suited to the airplane and along with the toe brakes fairly easy to modulate well though compared to today's usage of brakes I would say they would be slightly difficult to use for the modern pilot. The way I was taught was that they were to be used for directional control during taxi and to hold it still during run-up. They were very powerful and had an ever changing pedal travel input point for reaction. Modulation was sometimes sudden and grabby, so I developed a single brake application technique when using them on rollout by using the downwind brake to correct for weathervaning after hitting the stop with rudder and aileron. Tapping the brake on and off to maintain directional control until a stop or taxi speed where the tailwheel was unlocked for turn off and then the typical taxi routine was again used. Because the stators and discs were different metals, the discs would expand and change the pedal position related to brake reaction, so each time one applied pedal it may get more sensitive the warmer the brake got, and after a long taxi or much use during a crosswind rollout it would react as if it was adjusted tighter.
The old Goodyear wheels were magnesium and very light, the brake assembly was relatively compact and the tires were slightly larger in diameter and footprint so carried the airplane slightly more nose high and enabled it to feel a little lighter on the tires especially in grass than the more modern replacements.
My parents D-17S had the stock Goodyear multiple disc system and always flew with a wheel/tire and brake assembly in the baggage compartment along with a gallon of hydraulic fluid, 5606 since it was a military airplane with compatible seals. Just in case.
The early replacements were from C-310 or Aero Commander, they never seemed to incorporate the changing of the low pressure/high volume master cylinder system so several pumps on the pedal were required to get anything out of the modern high pressure/low volume single disc brakes. These have smaller diameter, narrower tires owing to the same for the wheels and those wheels are heavier aluminum makeup. As time went on it seemed more airplanes incorporated a modern master cylinder system. Redline or Cleveland brakes I'm sure are a matched master cylinder/caliper design. The last airplane I flew regularly (a 1935 B-17R which originally had early Johnson Bar actuation for bladder type brakes) had Beech Duke master cylinders with Cessna 195 pedals actuating Goodyear single disc brakes as a field mod (done during it's '70s restoration) which worked well.
Modern single disc, multi pot caliper brakes are much easier to modulate and disapate heat much faster than the old Goodyear multiple disc brakes and so have become popular as the bronze discs and the specific shaped hydraulic seals became difficult to find. Later the originals had the wheels machined for an insert to adapt a modern O-ring in the place of the specific shaped seal. The originals were a high maintenance item in the '70s, though I flew one D-17S extensively in the '90s which still had the system, so a well designed system nonetheless.
Hope this helps.
Chris...
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