Nav/DP Question

[Vector4fun]

I'm a controller trying to figure out a problem which seems to crop up with CRJs from time to time. Please refer to the CENTEX 2 departure, http://www.airnav.com/depart?http://204.108.4.16/d-tpp/0501/00556CENTEX.PDF

Now, take the Navasota transition for example. Normal ops used to be a vector of somewhere between 60-70 degrees to intercept the outbound 088R. Then some of the Boeing drivers told me it was a bit easier for them to go direct a fix on the departure than intercept the radial on a heading. Just simply a matter of a few less buttons to push. No big deal to me, so some of us started using direct HOOKK. Works well for both of us, and gets you established on the transition before leaving our airspace, and out of the way of the BITER arrivals.

Now, what happens with CRJs from time to time, is the crew advises they don't "see" HOOKK or JAYJO on the FMS. Is that "normal", or operator error, or something else? (I'm not trying to flame anyone here, just trying to understand the problem.) Issue #2 is that, especially with CRJs it seems, a vector of, say 060 to intercept the 088R will sometimes result in a left turn of app 010 deg direct CWK. This is BAD because it puts the aircraft in the face of the BLEWE arrivals, or some other traffic.

So my question is, shouldn't the fixes HOOKK and JAYJO be displayed on the FMS if the departure was programmed correctly? Or are there "modes" where they might not be? I have been told that the FMS will try to turn the aircraft towards CWK if not managed properly when on a vector to intercept the radial.

I'm also curious if you guys have to look up the initial altitude and dep freq and set that up manually, or if either of those is automatically set for you when you load the departure?

Thanks in advance for any insightful replies. The problems are not frequent, but when they do crop up, seem to happen with CRJs much more than any other type.

 

[91100 100 set]

Well, I don't know anything about the CRJ avionics/autopilot, butwithall the RNAVs/FMS systems I've used, it is far easier to go directto afix than fly a head to intercept a course. I have seen afewautopilots that have a tendency to make a slight turn in thewrongdirection if you hit the LNAV button immediately after enteringdirectsomewhere in the FMS. It's almost like the FMS is still tryingtofigure out the angles and is feeding the autopilot bad info, butthisis usually not more than 10 degrees and it turns back in thecorrectdirection in less then 15 seconds. It can be eliminatedbyturning in the general direction of the fix with the heading bugwhilethe FMS figures it all out and once you're within 5 or 10 degreesof the correct heading then hitting LNAV. A little extra work, and somefolks might be lazy andjust hit direct on the FMS and LNAV on theautopilot and let theautopilot wander around until it settles out.

Regarding the fixes not showing up, I don't know. I have selectedadeparture and the FMS figures it starts at such and suchintersection,50 or 100 miles away, while there are fixes on the sameradial or coursemuch closer to the departure airport that ATC likes touse. In thesecases, you must refer to the paper chart and enterit manually. Again alittle extra work, and some folks might not wantto refer to the paperchart to figure out where the fix is. Againkinda lazy, but we are allguilty of that occasionally.

I'm not sure if this is what you were talking about, but it might bealittle insight for you. BTW, I took a double-take at the NOSchart(What the hell is this thing?). I haven't looked at one ofthose inyears!

 

[HMR]

Operator Error (just a good guess).

 

[328dude]

If you select the right departure, it should draw out the departure for you if your database is up to date. If the Cpatain is flying in this scenario on white needles and selects NAV, the A/C will probably default to the first fix on the departure and could cause a turn in the wrong direction.

If they don't see Hookk on the departure, they need to whip out the paper format and type it in if they don't have it out already.

Just looking at the departure, it's not to difficult and can't seem to find a reason why the FMS wouldn't fly it. More than likely, human programming error.

 

[SLOTH]

I would have to take a look at how the SID is presented in the FMS, but I would dare a guess that it is an operator error. And as far as I'm concerned, there is no reason to not have the Jepp plate out to ensure no foul-ups just as 328dude mentioned!

Sloth

 

[trip]

On the CRJ when you load cwk2 tnv transition hookk and jayjo should be in the flight plan, if not it might be a database problem that should be fixed (this happens but not often). When you give us a heading to join what probably happens is HDG is selected on the flight control panel with NAV armed to capture the transition radial, but CWK is still the active waypoint (naving to) and when NAV is selected to join the transition it captures and starts a turn toward to CWK. The pilots see this and say #@*& ! Then they go back to HDG mode, move CWK behind them on the flight plan and arm NAV again! Did this make any sense?
Altitudes and Freq. is read of the paper and put in by hand.

I once had a clearence out of AUS (westbound for SLC) fly HDG join a radial of of some vor to join a airway? Never could put that in the box, just went out green needles!

 

[328dude]

How about CWK088/+17


That el fix it.

Like Trip said, when in dought, "fly old school, fly the green"

Vector, if you come across this again, just tell them to fly green needles and figure the rest out later. Atleast you won't have to worry about turns into your arrival's.

 

[PastMmo]

vector4fun,

issue 1 - my guess is that the crew is not programming in the DP. if the DP is not in the fms, then the legs page shows cwk then tnv. so, it would appear to you that they are flying the departure (088r), but they are not. this would explain not seeing the fixes hookk and jayjo in the fms. most of the time the flight plans do not list the DP's on them, so they could be just referencing the flight release and not listening to the actual cleareance when programming the fms.

issue 2 - i agree w/ what trip said. if the runway has not cycled in the fms, then it wants to fly or intercept a radial between the departure runway and cwk. this would explain the intial turn to approx. 010deg when the pilot selects 'nav'. this is independent of whether or not the DP is programmed correctly. if the runway has cycled, then cwk is the from waypoint, and 088R is the route. whether or not the runway has cycled in the fms depends on a/c position and departure runway.

 

[TonyC]

Based on what trip said, it sounds like they use a process almost identical to the MD-11 that I explained in your previous thread. There's no excuse why they shouldn't be able to comply with Heading 060 to join the 088R outbound, with or without FMS. With the FMS, it's 2 keystrokes more than proceeding direct to HOOKK or JAYJO.

Tell 'em to stop their whinin' and earn their paychecks.

If they don't know where HOOKK is, send 'em to the CWK 088 at 17DME fix. That'll show 'em!





Where do those CRJ guys get their "training"?!?!?

 

[Sc00ter]

Vector4Fun, how long have you been at AUS? Has xpdr 0274 brought you guys tacos in a while???

scoot