Flight director set up on T/O

[svcta]

Hey gang,
I have a question for those of you with Pro Line 4 EFIS. The subject of how to properly set up the flight director for take off has been swirling around my department lately and I'd like to get a better handle on it myself. Situation:

With Pro Line 21 there was a TO/TO mode activated by clicking the TOGA buttons. My understanding with that system was that TO/TO was simply a function of the flight director that propagated a Roll and Pitch mode along with aligning the FMS with the end of the runway that it was told to depart from. We took off in this mode and kept it there until 400 feet, at which point we would switch to Heading and some other mode of vertical guidance, typically Speed Mode (or FLC). This gave excellent guidance in every situation that I saw; V1 cuts, or normal t/o. It was trained that way by the factory.

Now I'm on an a/c with Pro Line 4 and there is no Take Off mode for the flight director. I've always been in the habit of using Roll and Pitch mode for T/O and have continued to do so. Reasons:

It sure is nice when you're given a heading to fly and you can preset it. "400 feet": "Heading mode, please" and away we go, no questions asked.

Heading mode won't compensate for wind drift any better than roll mode, and it will in fact command roll input to whatever degree it feels is appropriate to a distressed, slow airplane to maintain heading. This alone I view as a pitfall of heading mode.

Since the whole profile that I use involves switching to heading mode @ 400 feet anyway, I believe that I'd rather have wings level to that point (close to the ground and trying to build energy) than I'd like to maintain a flawless heading, regardless of the bank angle that is required to do so.

The question before the gallery is this: according to some, there is no protection with Roll mode to ensure that the a/c remains in the clearway of the take off runway. With this I agree. However, I think that it's better to wait a 10 or 20 seconds (if that) and get some speed and altitude behind us before we do much banking for headings with no degree of protection with respect to how far over we go.

In the airplanes that I flew with Pro Line 21 we would use half bank during single engine stuff.

In any event, what are the thoughts on this?

 

[Pickle]

On the HS-125 with Proline 21 we teach HDG and PITCH for takeoff, with the PITCH rolled up to 12 degrees. (I don't think 12 is enough though).

My .02.........

 

[400A]

Flight Safety taught in the Beechjet with Pro-line 4 to set runway heading and then to press the pitch sync button as you rotated to 8-10 degrees. We used to set the heading in the SDU to the assigned departure
heading as a reminder. After 8 years in the Beechjet it took a while to break this habbit.

In the Hawker and the Premier with Pro-line 21 they taught us to set runway heading (a few said pitch) and pre scroll the V bars to 10 degrees in the Premier and 12 degrees in the Hawker.

 

[Coool Hand Luke]

Hey gang,
I have a question for those of you with Pro Line 4 EFIS. The subject of how to properly set up the flight director for take off has been swirling around my department lately and I'd like to get a better handle on it myself. Situation:

With Pro Line 21 there was a TO/TO mode activated by clicking the TOGA buttons. My understanding with that system was that TO/TO was simply a function of the flight director that propagated a Roll and Pitch mode along with aligning the FMS with the end of the runway that it was told to depart from. We took off in this mode and kept it there until 400 feet, at which point we would switch to Heading and some other mode of vertical guidance, typically Speed Mode (or FLC). This gave excellent guidance in every situation that I saw; V1 cuts, or normal t/o. It was trained that way by the factory.

Now I'm on an a/c with Pro Line 4 and there is no Take Off mode for the flight director. I've always been in the habit of using Roll and Pitch mode for T/O and have continued to do so. Reasons:

It sure is nice when you're given a heading to fly and you can preset it. "400 feet": "Heading mode, please" and away we go, no questions asked.

Heading mode won't compensate for wind drift any better than roll mode, and it will in fact command roll input to whatever degree it feels is appropriate to a distressed, slow airplane to maintain heading. This alone I view as a pitfall of heading mode.

Since the whole profile that I use involves switching to heading mode @ 400 feet anyway, I believe that I'd rather have wings level to that point (close to the ground and trying to build energy) than I'd like to maintain a flawless heading, regardless of the bank angle that is required to do so.

The question before the gallery is this: according to some, there is no protection with Roll mode to ensure that the a/c remains in the clearway of the take off runway. With this I agree. However, I think that it's better to wait a 10 or 20 seconds (if that) and get some speed and altitude behind us before we do much banking for headings with no degree of protection with respect to how far over we go.

In the airplanes that I flew with Pro Line 21 we would use half bank during single engine stuff.

In any event, what are the thoughts on this?

As a former TCE with one of the two major training companies I can say that in my program we did not teach the method you mention.

We advised our clients to use a flight director command pitch (note that this is not the same as a TOGA FD pitch) as recommended by the OEM until such time as the pre-determined V2 speed FOR THAT SPECIFIC T/O was reached (hopefully at 35' AGL and the gear in transition) at which point selecting FLC mode for vertical guidance ensured maximum aircraft performance. Additionally, we recommended lateral guidance as provided by the heading mode as opposed to the "wings level mode", as simply being "wings level" in low vis (800, 1000, 1200 RVR etc.) with asymmetrical thrust and at the FAA required maximum allowable crosswinds used in FAR part 142 simulator training often resulted in aircraft heading deviations of 20+ deg. from that of the takeoff runway heading. This is insidious, as numerous slight (5-10 deg) heading deviations often go unnoticed but over the course of just a few minutes an aircraft can be considerably off course and outside the FAR part 77 provided safety area(s) (not to mention any TERPS obstacles) all the while the FD is providing a visual cue of a wings level condition.

For these reasons, I recommend that you use the FD heading mode.

 

[svcta]

In the time since I flew the CRJ I've been typed in two other jets. Neither of which included any real guidance on how to set the thing [flight director] up. Bombardier trained us to use TO/TO on the Pro Line 21 as installed in the CRJ and as far as I know every operator uses this mode for takeoff. It offers nothing more than Roll mode guidance and Pitch(which I'm less concerned with). Our company profile, though, was to select heading mode or nav mode at 400' depending on which type of departure we were on. In the case of single-engine, though, when either of these modes were selected the use of 1/2 Bank was mandated in order to prevent the aircraft from being over banked while in such a state of being behind the curve.

More to the point: In the case that you use for the crosswind above, CoolHandLuke, Heading mode will not offer any protection to wind drift, either. Factoring out the affects of assymetrical thrust (which should be minor), as long as the wings are kept near level, there should be no greater problem associated with drift as there would be in Heading mode.

My opinion is that a profile like the one that I cited above is about the best of both worlds. And I'm once again in an airplane that is under-winged (as was the CRJ-200). My feeling is that it may be best to avoid situations of higher angles of bank when you're within 400' of the ground and behind the drag curve the way that we are before we can begin to clean the wing (at 400' and V2 +10).

 

[ROSWELL41]

In the CRJ-700 (with Proline 4), we just hit the TOGA's before T/O. The flight director is enhanced and sets the appropriate pitch and aligns with the selected heading. In the CRJ-200 (also Proline 4), we hit the TOGA's, but now must use the V/S button to set the command bars at +10 degrees pitch up for takeoff due to a new airworthiness directive.

 

[svcta]

I guess that was Pro Line 4 on the CRJ, just with a completely different presentation than ours on the G-200. Nevertheless......

 

[Brett Hull]

I set the FD to the default 9 degrees with the TO/GA, and then bug runway heading and engage heading mode (unless it' a nav departure) on the Lear 60 PL21.

 

[FastestPA31Ever]

In the 50EX we generally depart in HDG - PIT mode, with the pitch set at about 15 degrees (or something close to what UltraNav tells us). Sometimes for more complicated DP's with multiple altitude gates leading to a level off altitude we'll arm NAV and VNAV (shows under HDG - PIT as armed in white) and then it will automatically capture through 400'. Initial level-off altitude set in the ASEL.

 

[Rythm3]

In the DA2000, we also use HDG/PIT with 11 degrees pitch up.

Some guys I fly with like to Takeoff with raw data, and hand fly until cleared on course. I do this on occasion; helps keep your scan sharp.

 

[ksu_aviator]

Valid arguments exist against using a flight director during takeoff. These arguments are especially valid if the flight director does not give you accurate information.

With fd's that have a takeoff function, the computers do compensate for a wide range of flight conditions and are a very good back up. Of course, and I doubt I have to say this, nothing substitutes for a good scan.

With fd's that don't have a takeoff function, the fd can, in certain situations, give confusing/misleading information. I would be very cautious of using a fd to give you information when the validity of that information could be in doubt.

 

[svcta]

All good points so far, but it seems like the answers are more focused on the Pitch setting of the FD rather than the Lateral mode. My questions concern the philosophy of setting the Lateral mode of the FD when a "TO" mode is absent.

What I'm driving at is "what mode do you use and why?" with respect to the lateral mode of your FD on takeoff.

Thanks and keep it coming!

 

[ksu_aviator]

All good points so far, but it seems like the answers are more focused on the Pitch setting of the FD rather than the Lateral mode. My questions concern the philosophy of setting the Lateral mode of the FD when a "TO" mode is absent.

What I'm driving at is "what mode do you use and why?" with respect to the lateral mode of your FD on takeoff.

Thanks and keep it coming!

None. If you assume that pitch mode is not accurate, why confuse yourself with having a FD that is only 1/2 right?

I personally fly using visual reference (when possible)to maintain the runway center line to 50 feet and then assigned heading after that. The FD does not come on until 400 feet (or acceleration altitude).

 

[svcta]

With respect, I think that you've misunderstood the question. I completely trust the pitch mode of the FD. If I set it to 11 or 12 degrees I believe that that is where it should be for a good first whack at getting me to a pitch angle that will give me the correct airspeed for a climb during an engine failure. My original question is posted above in an earlier post regarding what the best lateral mode for the flight director during an engine failure after V1.

See above for my thoughts on Heading mode VS. Roll (or TO/TO, if installed). It's a matter of which is more important until the 400' mark: Wings level and aircraft control, or following the FD to maintain a specific heading (as would be directed by an FD in Heading mode).

 

[batsky2000]

I have flown Collins,Honeywell,and Smiths(Boeing/Airbus). I currently fly a Challenger 604 and G-IV. The Challenger has a Proline 4, and the G-IV has a Honeywell SPZ8000. The Collins is the first system that I have ever trainied with that you hit the TOGA button, and take off in ROLL mode. I asked why we don't arm HDG or NAV mode, and the Flight Safety answer was that is how it is done, no other answer. I have since found out that there is no reason why you can't select a Lateral Navigation Mode. So every time I fly, I select HDG or NAV, and NAV mode works great if you have a RNAV Departure, it arms HDG then after you rotate goes into NAV mode. I have always selected some kind of Leteral mode on every other aircraft that I have flown. Evertime I fly the G-IV I hit TOGA then HDG or NAV, same thing on the B737...So try it, works fine and there is NO LIMITATION saying you can't do it!!!

 

[matchthehatch]

Two scenarios

I understand where svcta is coming from and makes a valid point regarding roll control in a low speed, low altitude situation. Imagine the following two scenarios involving a G200 at MGTOW, departing from a high-altitude airport on a hot day (a worst case scenario):

Selecting ROLL (wings level)
In the event of a failure of the left engine, the pilot will have to apply full right rudder. This alone will not allow the pilot to maintain runway heading, and he will end up somewhere to the left absent a bank of up to 5 degrees to the right, i.e. following the wings level command. If you factor in a crosswind from the right, he will end up even further to the left due to drift.

Selecting HDG
In that same condition, the pilot should be able to maintain the runway heading, as long as the crew has set the heading bug to align with the runway. The command bars will direct the pilot to maintain the runway heading. While the drift will still occur, the pilot stands a better chance of remaining in the protected area. Now I suppose it is possible to drag a wing, but the pilot would have had to have made a huge mistake before rotation by not setting the heading bug correctly, or by rotating the airplane while heading off of the runway.

For both flight director modes, remember that in the high and hot condition, the airplane is going to spend a much greater distance while climbing to an altitude at which it is safe to retract flaps. That 400' altitude requires a lot of horizontal distance to reach, subjecting the crew to a greater risk of leaving the protected environment.

 

[svcta]

You seem to understand the point that I'm making (perhaps a little too well, hmmmmmm) but I'm still not convinced that in the "hot and high" scenario that you present that it isn't that much important to handle the airplane gingerly at that point. Read that as: Hot and heavy = behind the curve. You've never told anyone to blindly chase any one single parameter in this regime of flight. When you're heavy, slow and managing a failed engine, you fly gently.

I think that we can agree on that as being sound advice. So if you would agree to disregard a flight director that was commanding a 30 deg. bank to reestablish a proper heading then I'd agree to add a little extra roll against my FD command in order to maintain the same heading. This would keep you closer to the command bars and should maintain the same heading. All the while doing it with better FD guidance than with HDG mode and with assurance that the aircraft won't be shedding lift because of higher than necessary bank angles to myopicly chase a heading.

HDG mode at 400', until that point I'd rather do my best to keep the wings level and gently manage my heading. This goes way back to basic fundamentals of aircraft handling. I routinely fly airplanes on the ragged edge of too slowly (props with parachutes on) and it is AMAZING how much lift you loose when you start aggravating a slow wing with ham fisted aileron input. Sometimes its the difference between flying and falling. Not that we're that close in our listed scenarios, but......why take a chance when you have this knowledge?

Obviously, it's still open for discussion.....what say the rest of you?

 

[matchthehatch]

(Fingers in ears)...I can't hear you. What did you say?

Let's call it pilot technique.

 

[svcta]

the above slightly edited for reread....

Honestly I think it goes a little deeper than technique. Not MUCH deeper, but a hair.

Unless we've established that we (neither) aren't really honoring the FD to begin with. Maybe we should turn it off in this case......

 

[batsky2000]

In all my years as a check airman, I have never seen soo much bable on such a non event subject. To pass your type ride or p135 check you must maintain runway heading per pts standards, or follow a SID if you are cleared for one. If you are that worried about hitting the wing to keep the wings level, then you have more problems than that. A V1 cut should be a non-event. When you hear V1, stay on the runway till you are staright and rotate, at that point, you should be wings level, no need to turn, if you loose an engine and rotate right after V1, then yes it will be a wild ride. I see too many people rotate after they loose an engine at V1, and they are all over the place. Hitting HDG and setting runway heading in your HDG bug will keep you staright, it does not limit you for anything