Primary and secondary hydraulics

[number3]

I've noticed that when i take damage, if the hydraulics get damaged both the primary and secondary are damaged and leaking at the same time. It never seems to be the case where one of the systems gets damaged while being able to still use the other.

 

Anyone know whether these two system are actually separate from each other? Or have you have one system fail and the other still functional?

[esb77]

There is a left hydraulic system and a right hydraulic system, and they are separated for redundancy.

 

Some of the more demanding systems will not function with less than about 50% total hydraulic capacity, the landing gear for example.

 

So having one system at 100% works or both at 50% works. I've flown with one system completely dead many times.

 

If you notice damage to the hydraulics it's a good idea to get the plane configured however you want it for the rest of the flight, because once you loose too much fluid either controls will not operate, or even worse, can get stuck partially or unevenly deployed.

 

Key systems are landing gear, flaps, and airbrakes.

 

Landing gear is the most demanding on the hydraulics system, but if you're far from base you need to consider if deploying the gear before you loose pressure will cause too much drag to get back to base safely. Belly landings tend to cause fire and then explosion, unless you've dumped fuel so that you land with empty tanks.

 

Air brakes are not advised if you have severe hydraulic damage. You can wind up with one brake closed and one stuck open, which causes terrible problems with yaw control.

 

Flaps are less of a problem if they deploy unevenly, the yaw and roll are annoying but not a big problem. Maneuvering setting gives enough extra lift so that you can do a slightly faster than normal landing, but is easier on fuel reserves if you're trying to get a damaged plane back to base with full flaps.

 

 

Most of the time if you get hit with an anti-air missile both hydraulics systems will be damaged. That's pretty much what the warhead on those missiles are designed to do. When I see only one system go down it's usually from AA artillery. The damage is less spread out and thus less likely to hit both lines.

Edited January 23, 2014 by esb77