What are the use case scenarios for Emergency Brake

[72hundred]

Hi,

 

I've googled and looked at the NATOPS manual (page 139 - I-2-67). I can't explicitly find a use case scenario. Is it just a back-up system for brakes in case of battle damage? How would I know that the regular brakes aren't working? Basically my question is what is the use case scenario!

 

Thanks!

[Swift.]

The emerg brake is used for when the normal hydraulics to the brakes aren't available. Afaik the brakes are powered off of the HYD 2A system, so if you get a HYD 2A caution then expect the brakes to not work in normal operation.

[Retu81]

Not applicable to DCS, but emergency brake is also used during towing operations on the ground. One person sits in the cockpit, ready to stop the aircraft, in case the towing connection breaks or the jet is about to hit an obstacle.

[X-31_VECTOR]

IIRC, it can also be used in the case of an anti-skid brake failure. It happened more than once in both Navy and Marine Corps fleets that a pilot would get an anti-skid brake caution and not do what the NATOPS says, which was something to the effect of turn off anti-skid and then brake gently without anti-skid (runway landings obviously, not ship).

 

If the anti-skid failed and the system was not turned off, upon landing the unlucky pilot would have no braking. Options then were to drop the hook and catch the runway arresting wire (if it was rigged and the pilot reacted in time); use emergency brakes; or put on power and take off again, then sort out the problem in the air.

 

If the pilot did none of those things and just tried to stand on the brakes, he might hypothetically roll through a chain link fence at the end of the field and eject while doing so, with predictably injurious results. You can find that one somewhere in the Naval Safety Center records if you want the whole sordid tale.

 

Anti-skid failure was mainly an issue when a/c that had been on the ship for several months were flying to terra firma. The electrical cabling that services the anti-skid system at the wheel ran down the outside of the gear strut, and could be damaged over the course of a tour with tie-down chains and the like. The first time the anti-skid was turned on in months (since it was not used aboard ship), one or more pilots might discover that the anti-skid was non-functional.

 

The pilots I worked with regarded it as a non-issue if the NATOPS was followed, and were pointedly unsympathetic toward the few souls who had mishaps because they didn't follow it.

[72hundred]

The emerg brake is used for when the normal hydraulics to the brakes aren't available. Afaik the brakes are powered off of the HYD 2A system, so if you get a HYD 2A caution then expect the brakes to not work in normal operation.

 

 

Cheers. That would agree with the NATOPS manual which states the emergency ones are off HYD 2B.

 

But I'm still not clear when to use it? Like is it for field landing? But there's no info on warning panel to tell me that 2A isn't working (https://imgur.com/a/gkfCQRH) - am I meant to just react in the case of nearly running off the end of the runway?

 

[G B]

Cheers. That would agree with the NATOPS manual which states the emergency ones are off HYD 2B.

 

But I'm still not clear when to use it? Like is it for field landing? But there's no info on warning panel to tell me that 2A isn't working (https://imgur.com/a/gkfCQRH) - am I meant to just react in the case of nearly running off the end of the runway?

 

 

You will get a HYD 2A caution on the DDI. The accumulators power the E brakes and those are partially charged by trickle charge circuitry in the HYD 2B system.

Edited February 21, 2020 by G B