When would you use the emergency disconnect paddle on the stick?

[titanium]

I just got the VKB F-14 stick and it has the emergency disconnect paddle replicated. I have been flying Heatblur's F-14 since it came out and have never used the the emergency disconnect before. The manual doesn't really say when it should be used just that it turns off all autopilot and SAS. When/Why would I want to do that? I'm thinking of using it for brakes instead.

[Xenovia]

When you're about to merge unexpectedly, is my guess.

[TLTeo]

It's really odd that it disables pitch as well as roll SAS. If it was roll only, then it would make sense going into the merge, but with pitch too it really is unclear.

[Skysurfer]

I think it's like with the Hornet, if you are about to CFIT or need to dump the autopilot in an instant for whatever reason. Other than that don't touch it.

[r4y30n]

It's really odd that it disables pitch as well as roll SAS. If it was roll only, then it would make sense going into the merge, but with pitch too it really is unclear.

 

Well, you need all three channels on for the AP to work, so it would make sense that an emergency disconnect kills all of them. I just assumed there was a nonzero chance the AP goes nuts and starts an uncommanded dive or climb so they put a handy switch in to quickly regain control.

[draconus]

 

Well, you need all three channels on for the AP to work, so it would make sense that an emergency disconnect kills all of them.

 

Not all - only 2.

[Spiceman]

The NATOPS are very confusing on the behavior of the SAS switches when the paddle is depressed. It is certain that depressing the paddle momentarily disengages the pitch and roll servos. There are conflicts between NATOPS on whether it disengages the pitch and roll SAS switches. The preliminary A NATOPS from the 70’s clearly says no. The A Plus NATOPS from 2001 clearly says no. The B NATOPS from 2004 clearly says no. The A NATOPS from 1997 says yes, or at least is really confusing and leads one to think yes. So, the jury is not out but it sure looks like the SAS switches should not be disengaged by the paddle switch.

[kengou]

My guess is this would be used in a departure from controlled flight situation, when you need full command authority to regain control.

[Skysurfer]

My guess is this would be used in a departure from controlled flight situation, when you need full command authority to regain control.

 

Yeah no, spin recovery dictates all SAS witches should be ON. You dont touch the paddle in that case.

[Spurts]

Spin recovery under 15,000ft dictates grabbing a yellow and black handle and pulling hard. Okay, it might be a bit lower than that.

 

[Golo]

You have all the control authority you need in F-14 to brake it in half, no point even thinking about the paddle.

Only thing I would use it to disconnect AP/SAS is if it had malfunction and did something unexpected, like pitch/roll that I did not initiate. Paddle would be my go to switch for that.

 

[Skysurfer]

From the NATOPS: "Disengages all autopilot modes and DLC. Releases all autopilot switches. Depressing the paddle switch reverts throttle system from AUTO or BOOST mode to MAN mode only while depressed and with weight on wheels."

 

It also seems like on later DFCS birds the paddle did not disengage the ROLL and PITCH SAS or DFCS.

[captain_dalan]

Oddly enough i use the paddle before every merge. Probably breaking a shitload of op in the process. But i find that the lack dampening in the pitch is a non issue for me.

[Spiceman]

Releases all autopilot switches.

 

Another point of confusion is that many people think this is referring to the SAS switches. It’s not.

 

[Skysurfer]

 

Another point of confusion is that many people think this is referring to the SAS switches. It’s not.

 

It does dump roll and pitch sas on older iterations. As I said, my quote is from the 97/2004 14A manual with DFCS. Gotta remember our cat is a mid 80's to mid 90's model.

[Spiceman]

Well, again, it’s not as simple as it did before and now it doesn’t. The F-14 Preliminary NATOPS from the pre-deployment 1970s clearly stated it did not disengage the switches. Even put it in a big Note paragraph.

[Golo]

Preliminary should be the clue here.

For the F-14A 01-F14AAA-1 Change 1 1997 clearly states that autopilot emergency disengage switch disengages all autopilot functions, DLC, Releases all autopilot switches, disengages pitch and roll servos and causes pitch and roll SAS switches to move to OFF position.

For the F-14B with DFCS 01-F14AAP-1 2001 states autopilot emergency disengage switch disengages all autopilot functions, DLC, it does not disengage roll and pitch SAS, it has to be done manually. Then again I belive our F-14B does not include DFCS.

[QuiGon]

Then again I belive our F-14B does not include DFCS.

That is correct.

 

 

[Victory205]

Most common/critical use would be to dump the autopilot in an emergency (like a Mode I gone divergent) or a throttle runaway on deck.

[Spiceman]

I’ve been hoping you’d weigh in. Did it disengage the SAS switch solenoids in the buno’s you flew?

[Victory205]

I’ve been hoping you’d weigh in. Did it disengage the SAS switch solenoids in the buno’s you flew?

 

The paddle switch disconnected the Pitch and Roll solenoids which was reflected by the physical switches moving to off. The Yaw switch was gated and stayed engaged. To disengage Yaw SAS, the pilot had to lift the switch to move it to the off position.

[Spiceman]

Thanks! That certainly settles the issue for the models you flew. I’m looking at a 2004 F-14A NATOPS that says “Depressing the autopilot emergency disengage paddle on the control stick (Figure 2-60) disengages the autopilot and DLC only. The PITCH, ROLL and YAW SAS switches and functions will remain engaged.”

 

Do you think this changed at some point (some version of FCS?) or perhaps the NATOPS wording is just misleading there?

[Skysurfer]

Thanks! That certainly settles the issue for the models you flew. I’m looking at a 2004 F-14A NATOPS that says “Depressing the autopilot emergency disengage paddle on the control stick (Figure 2-60) disengages the autopilot and DLC only. The PITCH, ROLL and YAW SAS switches and functions will remain engaged.”

 

Do you think this changed at some point (some version of FCS?) or perhaps the NATOPS wording is just misleading there?

 

That NATOPS is for a DFCS jet. Reference the flight controls section.

[Quid]

 

That NATOPS is for a DFCS jet. Reference the flight controls section.

 

I think Skysurfer got it; the 1997 Change 1 version includes the following: "Disengages all autopilot modes and DLC. Releases all autopilot switches. Disengages the pitch and roll servos and causes the pitch and roll SAS switches to move to OFF. The yaw SAS channels in either case are not affected..." So, that must have been a change around the time DFCS was coming online. The 1984 Change 1 version indicates this started with Airframe Change 400: "On aircraft BUNO 159859 and subsequent and aircraft with AFC 400, disengages the pitch and roll servos and causes the pitch and roll SAS switches to move to the OFF position. The yaw channels in either case are not affected."

[Spiceman]

Yeah, it’s weird that the paddle originally did not disengage the switches (ref preliminary NATOPS), then for whatever reason it did, then it didn’t again (ref -A circa 2004 and -A+ circa 2001). They must have been giving the pilot a way to protect against issues discovered in the early FCS then decided it could do more harm than good when the DFCS came along.