Today I departed out of RIL as a passenger on a Citation V Ultra being
flown under Part 135. Despite the winds and terrain favoring a
departure from runway 26, we departed runway 8. One of the consequences
of this was that we needed a 5500 foot ceiling, which we darn near
didn't get and we almost got stuck there.

When I asked why they departed runway 8 instead of 26 (whose departure
minimums require only a 3500 foot ceiling) I was told that the Honeywell
Primus 1000 FMS could not be programmed to properly fly the Squat 1
departure (http://204.108.4.16/d-tpp/0801/06741SQUAT.PDF). In
particular, the procedure requires that the plane fly to YIRDU
intersection before turning towards SQUAT, but the Primus 1000 always
interpolates its turns (i.e. it would start turning towards SQUAT
slightly before reaching YIRDU), and this cannot be overridden.

This all sounded a little farfetched to me. Leaving aside the fact that
it's only a 15 degree turn, I don't understand how any IFR-certified GPS
(let alone one that they would install on a freakin' jet) could not
properly fly a published GPS departure procedure.

Can anyone here shed any additional light on this situation? Is this
really true, or did I get told a tale?

Thanks,
rg

Ron Garret wrote:
/snip/
>
> When I asked why they departed runway 8 instead of 26 (whose departure
> minimums require only a 3500 foot ceiling) I was told that the Honeywell
> Primus 1000 FMS could not be programmed to properly fly the Squat 1
> departure (http://204.108.4.16/d-tpp/0801/06741SQUAT.PDF). In
> particular, the procedure requires that the plane fly to YIRDU
> intersection before turning towards SQUAT, but the Primus 1000 always
> interpolates its turns (i.e. it would start turning towards SQUAT
> slightly before reaching YIRDU), and this cannot be overridden.
>
> This all sounded a little farfetched to me. Leaving aside the fact that
> it's only a 15 degree turn, I don't understand how any IFR-certified GPS
> (let alone one that they would install on a freakin' jet) could not
> properly fly a published GPS departure procedure.
>
> Can anyone here shed any additional light on this situation? Is this
> really true, or did I get told a tale?
>
> Thanks,
> rg
Ron,

I'm not sure what they were trying to tell you, but there are no "fly
over" waypoints on this procedure, they are all "fly past", i.e. it's
perfectly acceptable (and expected) to anticipate any turns. Yes, any
competent FMS can handle this easily (though, I'm not familiar with the
Primus 1000 specifically).

Which direction was your destination? If it was eastbound, this
particular procedure takes you quite a bit out of your way. Perhaps the
crew wanted to save gas/flight time by departing 8. That doesn't make
much sense, though, if it meant a real possibility of getting stuck
there, instead of actually departing. Not only that, but both of the
Rwy 8 DP's allow a 400-1 takeoff minimum, assuming you can maintain 320'
per NM on the climb out, something I would think a Citation could handle.

Happy Flying!
Scott Skylane

In article >,
Scott Skylane > wrote:

> Ron Garret wrote:
> /snip/
> >
> > When I asked why they departed runway 8 instead of 26 (whose departure
> > minimums require only a 3500 foot ceiling) I was told that the Honeywell
> > Primus 1000 FMS could not be programmed to properly fly the Squat 1
> > departure (http://204.108.4.16/d-tpp/0801/06741SQUAT.PDF). In
> > particular, the procedure requires that the plane fly to YIRDU
> > intersection before turning towards SQUAT, but the Primus 1000 always
> > interpolates its turns (i.e. it would start turning towards SQUAT
> > slightly before reaching YIRDU), and this cannot be overridden.
> >
> > This all sounded a little farfetched to me. Leaving aside the fact that
> > it's only a 15 degree turn, I don't understand how any IFR-certified GPS
> > (let alone one that they would install on a freakin' jet) could not
> > properly fly a published GPS departure procedure.
> >
> > Can anyone here shed any additional light on this situation? Is this
> > really true, or did I get told a tale?
> >
> > Thanks,
> > rg
> Ron,
>
> I'm not sure what they were trying to tell you, but there are no "fly
> over" waypoints on this procedure, they are all "fly past", i.e. it's
> perfectly acceptable (and expected) to anticipate any turns. Yes, any
> competent FMS can handle this easily (though, I'm not familiar with the
> Primus 1000 specifically).
>
> Which direction was your destination?

Due west. Burbank.

rg

Ron Garret wrote:


>>
>>Which direction was your destination?
>
>
> Due west. Burbank.
>
> rg

Well, then I am at a complete loss. The appropriate DP in that case,
given a Rwy 8 departure, would be the EDUKY ONE. That DP is the only
one that *does* contain a "fly over" waypoint, the very thing your pilot
said his FMS *couldn't* do!

Happy Flying!
Scott Skylane

Ron Garret wrote:
> Today I departed out of RIL as a passenger on a Citation V Ultra being
> flown under Part 135. Despite the winds and terrain favoring a
> departure from runway 26, we departed runway 8. One of the consequences
> of this was that we needed a 5500 foot ceiling, which we darn near
> didn't get and we almost got stuck there.
>
> When I asked why they departed runway 8 instead of 26 (whose departure
> minimums require only a 3500 foot ceiling) I was told that the Honeywell
> Primus 1000 FMS could not be programmed to properly fly the Squat 1
> departure (http://204.108.4.16/d-tpp/0801/06741SQUAT.PDF). In
> particular, the procedure requires that the plane fly to YIRDU
> intersection before turning towards SQUAT, but the Primus 1000 always
> interpolates its turns (i.e. it would start turning towards SQUAT
> slightly before reaching YIRDU), and this cannot be overridden.
>
> This all sounded a little farfetched to me. Leaving aside the fact that
> it's only a 15 degree turn, I don't understand how any IFR-certified GPS
> (let alone one that they would install on a freakin' jet) could not
> properly fly a published GPS departure procedure.
>
> Can anyone here shed any additional light on this situation? Is this
> really true, or did I get told a tale?
>
> Thanks,
> rg

You got a tale, on a number of levels, plus I have to wonder about the
competence of that crew.

First, an IFR FME (or for that matter a panel mount) must be able to
handle both flyover (FO) and fly-by (FB) waypoints. There are two RNAV
DPs for Runway 8 and one for 26.

There is also a VOR/DME based ODP for Runway 8, but not for 26.

So, the basic takeoff minimums apply to the ODP for Runway 8 and to the
SQUAT RNAV DP for Runway 26. (26: 3400-3 or standard with a min CG of
360/NM to 10,000. 8: 5500-3 or standard with a min CG of 370/NM to 13,000)

The basic Runway 8 takeoff minimums do not apply to the two RNAV DPs for
that runway. They each have their own takeoff minimums and CGs. The
two RNAV DPs have the mandatory 400-1 requirement even with a CG,
whereas the "steam gauge" ODP is standard with its climb gradient.

Seems that they were not willing to do any of the three RNAV DPs, thus
opted for the steam gauge ODP.

Not a good choice at this airport. Runway 26 is downhill and with the
use of the SQUAT ONE there is virtually no terrain threat. In fact,
engine failure procedures off Runway 26 should be a piece of cake
compared to Runway 8.

SQUAT is a FB waypoint. The only FO waypoint for any of the three RNAV
DPs is USUNE.

Squat is speed limited so the turn doesn't occur two early for the AWRAW
or EDUKY transitions. There is no speed limit for the JNC transition
because there is a very small course change.

And, you say they needed a 5500-1 ceiling for Runway 8. True, but only
if they couldn't do 370 per mile to 13,000. If that airplane can't do
that, it shouldn't be doing IMC charters at an airport like Rifle.

Departing on the SQUAT on Runway 26 requires a slightly less climb
gradient and only to 10,000 feet, which is far less demanding.

I can only speculate:

Maybe they don't really know how to do RNAV DPs? Maybe their database
was out of date? Maybe they misunderstood the takeoff performance
requirements for each runway?

Bottom line: Anyone with their act together in an RNAV aircraft would
have departed Runway 26.

On Sun, 03 Feb 2008 08:44:52 -0800, Sam Spade >
wrote:

>
>First, an IFR FME (or for that matter a panel mount) must be able to
>handle both flyover (FO) and fly-by (FB) waypoints. There are two RNAV
>DPs for Runway 8 and one for 26.

I always learn from your posts... <G>

In article >,
Sam Spade > wrote:

> You got a tale, on a number of levels, plus I have to wonder about the
> competence of that crew.

I dunno. I grilled them pretty hard and they seemed to know what they
were doing. They didn't get defensive about it or anything.

> First, an IFR FME (or for that matter a panel mount) must be able to
> handle both flyover (FO) and fly-by (FB) waypoints.

The crew was quite specific that this one could only do FB, except with
an upgrade that the company was unwilling to pay for. (I even asked
them why don't they just hand-fly the DP, and the answer was that they
could, but that the CDI would still direct them according to the FB
routing, so that wouldn't actually help.)

> There is also a VOR/DME based ODP for Runway 8, but not for 26.

[xnip]

> Seems that they were not willing to do any of the three RNAV DPs, thus
> opted for the steam gauge ODP.

Yes, exactly. That is exactly what they said.

> Not a good choice at this airport.

That's what I thought, and that's what they thought. But they said that
according to the regs they didn't have a choice.

> And, you say they needed a 5500-1 ceiling for Runway 8. True, but only
> if they couldn't do 370 per mile to 13,000. If that airplane can't do
> that, it shouldn't be doing IMC charters at an airport like Rifle.

It can certainly do that with both engines, but with an engine out it's
dicey (this, again, according to the crew).

> I can only speculate:
>
> Maybe they don't really know how to do RNAV DPs?

Inconceivable.

> Maybe their database was out of date?

Possible, but that's not what they said.

> Maybe they misunderstood the takeoff performance
> requirements for each runway?

Ditto.

> Bottom line: Anyone with their act together in an RNAV aircraft would
> have departed Runway 26.

Yeah, that's what I thought.

rg

All the details aside, there is no RNAV system certified that won't
handle both flyby and flyover waypoints.

Such a limited system could not fly any GPS approaches, because they all
have a flyover waypoint to begin the missed approach.

So, you were being fed some kind of BS.

Also, as to Part 135 single-engine contingencies, they could have a
different procedure than the ODP for Runway 8, if their company chose to.

I will check out the Primus 1000 with some pilots that fly that system. ;-)

Did you note that the SQUAT 26 DP doesn't have any flyover waypoints?

I got the info.

What the crew told you was about right.

That model, as delivered from Cessna, is not RNAV-1 compliant.

It requires a couple of hardware mods/additions to become RNAV-1. So,
none of the RNAV stuff at RIL was avaiable to them.

Not the best configuration to dispatch to RIL in weather conditions.

In article >,
Sam Spade > wrote:

> I got the info.
>
> What the crew told you was about right.
>
> That model, as delivered from Cessna, is not RNAV-1 compliant.
>
> It requires a couple of hardware mods/additions to become RNAV-1. So,
> none of the RNAV stuff at RIL was avaiable to them.
>
> Not the best configuration to dispatch to RIL in weather conditions.

Un-freakin-believable. They build a $5M plane and don't even put a
decent GPS in it? Why would anyone buy it?

Thanks for looking into that for me.

rg

In article >,
Sam Spade > wrote:

> Did you note that the SQUAT 26 DP doesn't have any flyover waypoints?

I'm not actually sure how to tell the difference. I wansn't even aware
that there was a distinction before this whole incident happened. In my
Cirrus I just select the procedure on the Garmin and hit the NAV button.
:-)

rg

Ron Garret writes:

> Un-freakin-believable. They build a $5M plane and don't even put a
> decent GPS in it? Why would anyone buy it?

Because it's half the price of the same plane with the fancy avionics?

In article >,
Mxsmanic > wrote:

> Ron Garret writes:
>
> > Un-freakin-believable. They build a $5M plane and don't even put a
> > decent GPS in it? Why would anyone buy it?
>
> Because it's half the price of the same plane with the fancy avionics?

For that to be true, RNAV-capable avionics would have to cost $5M. You
can go to Cessna and buy a complete Garmin glass cockpit for about 5% of
that (and they'll throw in a nice carrying case called a 172SP as a
bonus).

rg

Ron Garret wrote:
> In article >,
> Sam Spade > wrote:
>
>
>>Did you note that the SQUAT 26 DP doesn't have any flyover waypoints?
>
>
> I'm not actually sure how to tell the difference. I wansn't even aware
> that there was a distinction before this whole incident happened. In my
> Cirrus I just select the procedure on the Garmin and hit the NAV button.
> :-)
>
> rg

The flyovers have a circle around them. You need to know only to the
extent that with a FO the Garmin won't lead the turn.

Ron Garret wrote:

> In article >,
> Sam Spade > wrote:
>
>
>>I got the info.
>>
>>What the crew told you was about right.
>>
>>That model, as delivered from Cessna, is not RNAV-1 compliant.
>>
>>It requires a couple of hardware mods/additions to become RNAV-1. So,
>>none of the RNAV stuff at RIL was avaiable to them.
>>
>>Not the best configuration to dispatch to RIL in weather conditions.
>
>
> Un-freakin-believable. They build a $5M plane and don't even put a
> decent GPS in it? Why would anyone buy it?
>
> Thanks for looking into that for me.
>
> rg

From what I'm told, the airplane is fairly old from a GPS-equippage
standpoint.

Ron Garret writes:

> For that to be true, RNAV-capable avionics would have to cost $5M. You
> can go to Cessna and buy a complete Garmin glass cockpit for about 5% of
> that (and they'll throw in a nice carrying case called a 172SP as a
> bonus).

A Garmin cockpit may go blank on you one day, and then you'll end up in a
mountainside. Avionics for commercial aircraft are somewhat more rigidly
tested and designed (although still not always well enough, in the case of
software).

Mxsmanic wrote:

> Ron Garret writes:
>
>
>>For that to be true, RNAV-capable avionics would have to cost $5M. You
>>can go to Cessna and buy a complete Garmin glass cockpit for about 5% of
>>that (and they'll throw in a nice carrying case called a 172SP as a
>>bonus).
>
>
> A Garmin cockpit may go blank on you one day, and then you'll end up in a
> mountainside. Avionics for commercial aircraft are somewhat more rigidly
> tested and designed (although still not always well enough, in the case of
> software).

Is that how it works in Flight Simulator, the Garmin unit fails and you
hit a mountain?

Bingo! Great game.

Sam Spade writes:

> Is that how it works in Flight Simulator, the Garmin unit fails and you
> hit a mountain?

No. In simulation, avionics never fail unless that is a planned part of the
simulation. The problem arises in real life, where inadequately tested
software may cause catastrophic and unrecoverable failures.

On Feb 5, 4:23 am, Sam Spade > wrote:
>
> ["context" removed, since any actual context had already been squelched]
>
> Is that how it works in Flight Simulator, the Garmin unit fails and you
> hit a mountain?

"This will end your Windows session. Do you want to play another
game?"

> Bingo! Great game.

Indeed. I enjoy it more than MSFS.