F-16.net

We hashed this out in a post long since forgotten, but Vipers, by nature of the FLCS, are generally not subject to the same AOA laws as other airfoils. In theory they most certainly are, but there is a computer that stands between reality and theory here. While for all aircraft AOA-crit is not dependent on airspeed, the Viper has to be manipulated such that AOA-crit falls below the limiter threshold which is a hard thing to do, and damned near impossible at any reasonable flying airspeed.

Also, the Viper does have nosewheel-steering, and differential braking is rarely used. Possible though.

As for the 'THROTTLE - IDLE' thing, I understood that Falcon 4 was a Block 52 replication, implying PW229 motor, and that's the incorrect procedure for a -229. It would probably work anyway though. I'm sure you can find the correct procedure out there (don't want to make this -too- easy for you by just telling you!)

F-16.net Sponsor

This message from our sponsor will disappear if you log on as a member.

Quote:

Also, the Viper does have nosewheel-steering, and differential braking is rarely used. Possible though.

So when you engage NWS do you command it with the toe brakes or by 'normal' rudder pedal movement? Interesting...

STBYGAIN wrote:

We hashed this out in a post long since forgotten, but Vipers, by nature of the FLCS, are generally not subject to the same AOA laws as other airfoils. In theory they most certainly are, but there is a computer that stands between reality and theory here. While for all aircraft AOA-crit is not dependent on airspeed, the Viper has to be manipulated such that AOA-crit falls below the limiter threshold which is a hard thing to do, and damned near impossible at any reasonable flying airspeed.

Right, but every airfoil has a critical alpha...every airfoil can and will stall at some point.

I remember one of the 'tests' the pilot would do on our UTD sims was to verify the fidelity of the aero model by putting the jet in the deep stall corner and rocking her out. It wasn't one of the 'formal' acceptance tests but they would always insist on it because they taught the recovery technique in the sims. You don't want your first time to be the real one...

Newbie Joined: Dec 09, 2003 Posts: 12 Status: Offline

A lot of aircraft these days are going towards differential braking to turn and not using steerable nosewheels. Even G/A aircraft. I guess this eliminates the possibility of damaging the steering mechanism while towing and also decreases weight since you have to have brakes anyway and you can eliminate the steering system. Plus, brakes are an easy thing to change.

F-16Rooster wrote:

A lot of aircraft these days are going towards differential braking to turn and not using steerable nosewheels. Even G/A aircraft.

Uh, this is not new....when you steer the pedals without using brakes, the nosewheel will steer....but you can also tap the toes and use brakes fo differential steering. This method is as old as time.

Elite Joined: Jan 31, 2004 Posts: 1496 Status: Offline

habu2 wrote:

Quote:

Also, the Viper does have nosewheel-steering, and differential braking is rarely used. Possible though.

So when you engage NWS do you command it with the toe brakes or by 'normal' rudder pedal movement? Interesting...

With NWS engaged, rudder pedal deflection turns the nosewheel (+/- 30 deg. if I recall). You can also get a slightly tighter turn radius by adding brake in the direction of turn coupled with the NWS, but I don't think they recommend it (might scuff the NW tire).

Diff braking is called for in cases where the NWS fails, like (conveniently enough) right before leaving the active or being marshalled out of the parking spot. The nosewheel essentially becomes a shopping cart wheel with diff braking. Consult your local checklist for details.

Elite Joined: Jan 31, 2004 Posts: 1496 Status: Offline

STBYGAIN wrote:

As for the 'THROTTLE - IDLE' thing, I understood that Falcon 4 was a Block 52 replication, implying PW229 motor, and that's the incorrect procedure for a -229. It would probably work anyway though. I'm sure you can find the correct procedure out there (don't want to make this -too- easy for you by just telling you!)

I'd think you'd want the engine at idle 'til you broke the stall to prevent a compressor stall during the rock-out. Most of the newer engines have nifty swifty DEECs that make clearing a stall somewhat easier than the older motors (PW -220 and before) but in a situation like that you'd have your hands full with tryin' to get flyin' again (and doubly so if you're inverted) without having to worry 'bout a compressor stall to boot.

Elite Joined: Jan 31, 2004 Posts: 1496 Status: Offline

habu2 wrote:

I remember one of the 'tests' the pilot would do on our UTD sims was to verify the fidelity of the aero model by putting the jet in the deep stall corner and rocking her out. It wasn't one of the 'formal' acceptance tests but they would always insist on it because they taught the recovery technique in the sims. You don't want your first time to be the real one...

I don't recall but do the UTDs have a dedicated Deep Stall scenario now like on the old WSTs? THAT was way cool 'cause with the touch of one button you could instantly shift the CG, put the kid in "trouble" (either upright or inverted) AND make it either survivable or not. Twisted Evil

Hey...he/she has to know when to eject and when to stay with it, right?

Newbie Joined: Dec 09, 2003 Posts: 12 Status: Offline

Habu wrote:

F-16Rooster wrote:

A lot of aircraft these days are going towards differential braking to turn and not using steerable nosewheels. Even G/A aircraft.

Uh, this is not new....when you steer the pedals without using brakes, the nosewheel will steer....but you can also tap the toes and use brakes fo differential steering. This method is as old as time.

I know you could always differential brake to turn the aircraft. But using the nosewheel to steer was the primary method. What I was saying is that modern aircraft do not have steerable nosewheels at all. The rudder pedals turn the rudder but not the nosewheel. Turning is achieved ONLY by differential braking.

Name one modern GA aircraft where this applies.

Try differential braking on a U-2... Mr. Green

Quote:

I understood that Falcon 4 was a Block 52 replication

In their dreams. The original Falcon 4 cockpit was at best a Block 30/32 with a LOT of artistic license. I worked at length with Xis and others to make 3rd party cockpits that faithfully replicated the Block 50/52 series. The entire engine/aero model has also been reworked by the 3rd party world to be much more realistic than the original F4 sim ever dreamed of being.

habu2 wrote:

Try differential braking on a U-2... Mr. Green

eh...the pogos don't have brakes;)

Quote:

eh...the pogos don't have brakes;)

My point exactly... Wink

F-16.net

Forum: F-16 Procedures

Deep stall recovery