What Value is a Flight Director

noahfong said:
As others have said, flight directors are great. But you have to know how to use it. It was a mystery to me until I flew for a regional (CRJ pilot). I'm finding out that most pilots don't know how to use a FD unless someone who has jet time showed them.



A FD-equipped G1000 would have an autopilot that depends on a functioning and "sync'd" FD. You would have to get the FD working in order to use the autopilot.
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Curious Noah, what do pilots with jet time teach over what pilots who don't have jet time teach. Not busting here, serious question.
 
noahfong said:
As others have said, flight directors are great..................... You would have to get the FD working in order to use the autopilot.
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And that was the weird thing about that:yeahthat: Bendix M4D flight director. You had to have A/P "ON" first! Then you could command FD................and THEN turn the autopilot back off.

Other strange things about that early King Air 65-A90. It didn't have bleed air pressurization. The right engine had a supercharger that provided pressurization.
 
PaulS said:
Curious Noah, what do pilots with jet time teach over what pilots who don't have jet time teach. Not busting here, serious question.
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You're right - I shouldn't have implied only jet pilots know how to use the flight director. It's just that I'm pretty sure they do but not to the exclusion of others. What I do find is that everyone I encounter who has not flown in a professional capacity in an aircraft equipped with a flight director and autopilot does not really know how to use it. I know this does not mean there isn't someone out there - I just haven't encountered them.

One of the flight schools I teach out of has a nice G1000 simulator (with a real G1000). I've yet to see anyone, including the flight instructors, use the flight director. It's either turned off or moved off into some corner of the PFD.

I am convinced that it is dangerous to try learning it by "hacking". There is a logic behind the FD functionality (all the different modes and annunciators). And learning it from someone who is properly trained is the best way.
 
noahfong said:
One of the flight schools I teach out of has a nice G1000 simulator (with a real G1000). I've yet to see anyone, including the flight instructors, use the flight director. It's either turned off or moved off into some corner of the PFD.
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How does one move the FD off into a corner of the PFD on a G1000?
 
I’ve known lots of non-professional pilots that were very proficient with autopilot and FD use/management.

sounds like @noahfong has worked around a bunch of puppies at the mill before getting that CRJ job.
 
If you learned to fly with them they are great. If you spent most of your flying life without them they suck, even with jets. They are not necessarily coupled to autopilot, and when they aren't I find them to actually increase workload.

Bottom line, I wish they had never been invented.
 
I've seen an interesting effect when teaching FD usage to my clients, who generally own their aircraft and are putting in new equipment (or learning how to use what they have). In order to accurately fly a FD, you have to use the tiniest of inputs. Like you should be doing anyway, but so many people overcontrol in normal flying. They just don't notice it because the needles (ILS, etc) stay more-or-less centered despite their back-and-forth control movements.

But with a FD, snugging it right up into a single-cue, or keeping the dot right on the crosshairs of a double-cue, takes very fine control, and even a small deviation can quickly become obvious.

Say your heading is just a bit off to hold the Localizer. You may correct 10 degrees one way, wait for it to stop moving, then correct back 5 degrees, etc. But with a FD, it knows that you really only need a 2.8 degree correction, and if you put the nose "right here" that will work. Same thing with glideslope.

So it can train you to make smaller, and more frequent corrections, even when it's not turned on.
 
RussR said:
I've seen an interesting effect when teaching FD usage to my clients, who generally own their aircraft and are putting in new equipment (or learning how to use what they have). In order to accurately fly a FD, you have to use the tiniest of inputs. Like you should be doing anyway, but so many people overcontrol in normal flying. They just don't notice it because the needles (ILS, etc) stay more-or-less centered despite their back-and-forth control movements.

But with a FD, snugging it right up into a single-cue, or keeping the dot right on the crosshairs of a double-cue, takes very fine control, and even a small deviation can quickly become obvious.
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Very good point. And nothing has really changed in terms of required input, it's just a lot more obvious how small those inputs need to be.

And when you start using a HUD those little roll and pitch nudges get even smaller...
 
BrianNC said:
As someone who has never flown a FD, and really don't know about them, don't most pilots just use the autopilot? I don't think I've ever seen anyone use a FD in a video. It's always the autopilot.
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The FD prompts are for hand-flying. They allow you do see your mistakes sooner, before the heading, course, altitude, or vertical speed has started to change, resulting in more precise control.

On modern jets, you can't engage the autopilot(s) if the FD(s) isn't on first. During most phases of flight (non-LOC MAP mode), we don't even have a course-deviation-indicator to navigate from. We navigate from the FD. (The LOC and G/S CDIs in my avatar are only there because the display is in ILS mode as indicated by the white "ILS" in the upper-left of the ADI. They disappear when an ILS freq is not tuned in the associated NAV radio. It also shows that the AP is engaged by the green "CMD" at the top-center. That would be "FD" if only the FD was engaged.)

The FDs, separate systems for each pilot, are turned on before engine start and almost always stay on until landing. The only time they are off is if there is a system failure or (rarely) the pilot-flying turns his off to practice flying without it.

Briar Rabbit said:
I am still wondering if it would be easier to fly ILS approaches by hand with the flight director in the Dual Cue format ... seems like that would more closely resemble the original CDI that was removed.
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The dual-cue FD is NOT a CDI. It does not present information in the same way as a CDI. It does not respond like a CDI. That is a very common mistake that pilots new to dual-cue FDs make and it causes them lots of trouble.

If the roll-bar is offset, it is not commanding a turn, it is commanding a roll. Similarly, when a pitch-bar is deflected, it is only commanding a change in pitch attitude; it does not mean that you are high or low. If the pitch-bar is deflected 5° above the current pitch attitude, it is NOT commanding a 5° pitch change. As you apply the commanded control inputs the deflected cue will return to center as you reach the bank angle/pitch attitude that it is commanding.

For this reason, a single-cue FD is probably easier for a pilot who is new to FDs. I find the split-cue to be easier to fly precisely, though, once you are comfortable using FDs.;
 
I learned with out one, and now use one, I love it and wouldn't give it up. BUT it's important to know when to shut it off, if you don't it will mess you up. One instance is in the pattern, no use there.
 
The larger the attitude indicator the easier it is to follow the FD commands. The small instruments in light GA aircraft make following FD commands a bit more challenging. It is still the same principle though it's just that the apparent deviation is smaller so harder to spot with the smaller instrument. I wonder if this is what happens with a HUD? I've never flown with one.
 
On my Stec 60-2, when the AP is engaged in both a lateral and vertical mode, the FD is also displayed. If the auto pilot disconnects, the FD indication is removed. To operate in just FD mode, one needs to turn on a FD master switch and turn the three position AP switch (On, Off, Test) to Off. When using the FD, you must still input the command on the AP annunciator/selector panel.
 
Anyone have an idea what the F/D expansion for a Century 2000 Autopilot costs and just what is it? A/P card? For my 182 and would display on GI275. Thanks
Tom
 
Larry in TN said:
The only time they are off is if there is a system failure or (rarely) the pilot-flying turns his off to practice flying without it.
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The only thing I'd add here (to a fantastic explanation, btw) is that at least at my company, the culture is to turn off the FD if you're not planning to adhere to its commands for any extended period of time. Generally in that case you'd tell the other guy to make whatever changes to the flight guidance panel to make the command bars match what you're doing, but sometimes it's easier to just say eff it and turn them off altogether.

A good example, which I have NEVER done of course, is forgetting to reset the altitude selector to the missed approach altitude on an approach that uses VNAV. "Wait, why is it trying to level me off - awww dammit - can you turn off my flight director?" :)
 
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kayoh190 said:
A good example, which I have NEVER done of course, is forgetting to reset the altitude selector to the missed approach altitude on an approach that uses VNAV. "Wait, why is it trying to level me off - awww dammit - can you turn off my flight director?" :)
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You don’t just try to pitch sync half a dozen times because you don’t nderstand what pitch sync is actually doing?:rolleyes:
 
MauleSkinner said:
You don’t just try to pitch sync half a dozen times because you don’t nderstand what pitch sync is actually doing?:rolleyes:
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Hahaha - we don't have pitch sync in the 737, but I remember it well from my Citation days.
 
Without a flight director I can usually maintain within 1/4 scale deflection on an ILS. With it I can maintain a 1/4 of a dot instead.
 
Larry in TN said:
I find the split-cue to be easier to fly precisely, though, once you are comfortable using FDs.;
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Once I tried dual cue, I liked it better than single cue. Luckily the last airplane I flew had a way to switch back and forth because the other guys liked single cue.
 
kgruber said:
My first flight director was a Bendix M4D add-on. It had two green balls and you were to superimpose the two red balls over the green.
Euj3t4.jpg
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My first corporate job was to fly a C310 and SIC on a Citation I. The C310 had the same Bendix FD as you posted. I think it was coupled to this autopilot head.

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Later I started flying a Falcon 20 that had Collins FD's. It had a rotary selector for hdg, vor, loc, ect.. The pitch part of the FD was controlled by a round knob that just moved the vbars up and down, they were not coupled to your altitude or GS. There must have been other controls for the autopilot because it would hold altitude but I can not remember how it was controlled. We hand flew all approaches so I cannot remember if the AP would couple to the ILS. I have never seen another system like that Falcon 20. I flew it in the mid 80's and it was probably built around 1970.
 
It’s really nice to have. It makes shooting an approach to mins a cakewalk
 
kgruber said:
And that was the weird thing about that:yeahthat: Bendix M4D flight director. You had to have A/P "ON" first! Then you could command FD................and THEN turn the autopilot back off.

Other strange things about that early King Air 65-A90. It didn't have bleed air pressurization. The right engine had a supercharger that provided pressurization.
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Our Cheyenne had one. As long as you knew it's limitations, it work OK. Had to disengage at TOC, set power and trim, say a prayer, then enter altitude hold and nav. Otherwise it would poipose and make the pax sick!
 
I'm probably in the camp of finding FDs more useful in turbine flying.

My Beech 18 has an FD and if you follow it, you are guaranteed to overspeed the flaps....
 
PeterNSteinmetz said:
But does it give you lower “secondary minimums”?
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Depends.

In a 135/121 program it can as part of a system allow lower minimums. Even in a Part 91, the FD coupled with an autopilot and also including a radar altimeter (there are some other items as well) along with additional training and checkride can allow the aircraft/pilot lower landing minimums.
 
I wouldn't want to fly w/o a FD if the AP is MEL'd; that would be exhausting. Just doing raw data in the sim once a year is enough for me.
 
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