Forum: F-16 Procedures

I'm hoping someone can help me with this. I'm building an F-16 flight simulator and have a question on the action of the Alt Gear Handle. How does the handle work in the actual aircraft? Does the handle stay out when pulled and if so how far out does it travel? Or does the pilot pull the handle and it snaps back to its original position?

Thanks,
Mike

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The handle stays out. And don't push the white button before pulling it Razz

According this -1 the ALT GEAR handle enables a pneumatic accumulator to open the LG doors and extend the NG. MLGs are gravity drop. The reset button is used to resume hydraulic control of the LG. The button is used after resuming the handle to the normal position, disconnecting the pneumatic supply, and allowing pneumatic pressure to discharge for the LG selector hydraulic valve to resume normal hydraulic operation.

There is absolutely no way to reset the Alternate Landing Gear Control Handle from cockpit. White button act as a guard against basic mishandling. The only way of resetting LG system once deployed by the pneumatic accumulator is by pushing back to its original position a pop-out protruding from Landing Gear Control Valve in L/H MLG bay.

In maintenance during checkouts:
After alternate selection and when the gear handle is still in up position, the gear can be reset by pushing back the alternate handle and by pushing the white button (few seconds)
I personally shall never try to reset the gear by pushing the button on the valve in the wheel bay , When a plane taxies in with the gear cycled down with alternate: install the three pins and dont touch anything with a running engine.

IIRC, when we trained Alt Gear Deployment in the old sims, the mains would freefall normally but the NLG would sometimes be delayed if the airspeed was still a skosh too high. The blow-down bottle didn't have enough umph to push past the airloads. Once the airloads bled off the NLG would eventually lock into place. I wanna say that threshold speed was ~ 170 knots but it's been years and I've slept since then. Wink

So when modeling your sim's gear you may wanna take that into account.

The speed is now 190 knots. However you can use the alternate gear handle already below 300 knots, but the time to 190 has to minimized so the nose gear can extend succesfully. Also there may be a reason to reset the atlernate gear handle during flight (eg. Alternate gear extention was unsuccessful) so th egear can be raised and you can land gear up for example.

gabrielk, sorry to tell you but you are wrong.
You are probably confusing between the white button on the regular Landing Gear Control Handle.
The white button on the Alt Gear Control Handle is used to reset the Landing Gear Control Valve to the regular position once there is hydraulic power in the B system.
If pushed in flight, when you have Hyd. Pressure in the B System, it will reset the valve and if the Landing Gear Control Handle was in the up position, the gear will probably retract again (not recomended since there is still nitrogen pressure on the other side of the hydraulic actuators, anyhow it will be a mess)...

Again you may need to use the reset button, because the alternate gear extention was unsuccessful. You will rather land gear up than with one main gear down. Who cares it is gonna be a mess in the wheel well.

Forum: F-16 Procedures

Alt Gear Handle operation