U36B Brakes

Those electric "parking brakes" (WTF?) have provisions to manually operate them, in the event of motor failure, or or drive failure. Yes, as stated, it is a "Non-Complying loco, without an OPERATIVE handbrake, and it cannot be accepted at interchange, or hauled in a consist, past the FIRST location where repairs can (and must) be made. In an emergency, such as this, you can attach a ratchet type brake, welded to the loco in any location where it can be safely operated from, and it must apply the brakes sufficiently to hold the loco from moving. Remember, a locomotive is still a locomotive, whether it's running, or dead. Subject to all parts of the CFR , Title 49, parts 223, 229, 231 and 232. The entire brake system must also be tested, and inspected, and certified for service, prior to acceptance at interchange. Sounds like a real "prize", you got there......

Parking brakes are applied by spring and released by air
you mean electric operated hand brake, the FRA distinguishes betweeen the two.
with Handbrakes it has chain to a mechaism and only affect two axles on one truck
The parking brake is a feature in treadbrake units and will apply on all brakeshoes on a locomotive. only way to release a parking brake unit on failure is with a wrench on release bolt on the treadbrake unit.

What "treadbrake" units are you refering to? most, if not all (excluding some Pax electric locos, that might use disc brakes)loco brakes are applied to the tread of the wheel. What loco, excluding some Pax unit, uses a parking brake that applies all of the shoes, against all of the treads? We are talking about a "typical" GE freight unit here, with one HANDBRAKE that pulls one shoe against the wheel, to hold the engine. There is no rule, or law, calling for a handbrake to apply brakes on 2 axles, on 1 truck. Having the Feb., 2006 edition of the CFR in my hands, I am not finding these things you are claiming, DRN. I have pushed many a button, while applying a handbrake, and only one shoe is applied, to one wheel. And yes, there is a crank to release/apply the brake, in event of failure of pump/motor. BTW, the fine for not having that hand brake, is $5,000.00 for "accidental" violation, and $7,500.00 for a "willful" violation. Willful meaning, of course, that you are aware the brake is missing, and are allowing the unit to travel. A "quickie" repair would be to weld ANY handbrake you can find, to loco body/frame at any truckframe location, and run a chain, and clevis to a piston, being sure the brake will apply, and release, as well as hold the unit stopped. Good Luck!!!

The Genesis series has parking brake with all shoes applied when air valve in cab is shut off, it takes air to release.
a freight unit is usually equippend with hand brakes(still called handbrake even if air or electric operated)

A tread brake unit has nothing to do with shoe/tread but its a self contained unit with one brake cylinger and ratchet mechanism .
The brakes gear instead of truck mounted is in the self contained unit behind brake shoe.

Where, might I ask, does that shoe appy itself? If it's applied against the tread..........