Cleared Direct Destination?

[avbug]

I never said it was a substitute, brightspark. Read the posts again.

I did say that a pilot who says it can't be done is suffering from a competency issue. The question was one of legality, and morphed into a discussion over weather it was possible.

For those who say it isn't, it is. To say otherwise is only to expose ignorance.

 

[Sctt@NJA]

Yeah and I hope everyone is up on their celestial navigation too. I can't believe how many people can't navigate by the stars! This is a basic navigation skill. If you aren't up on it you are incompetent. And if you dissagree with me then you are ignorant!

Sorry, just having fun. Feeling devilish.

 

[Hawker rider]

I might even go as far as saying that it is a substitute allright.

It all depends on the skill of the navigator, dead reckoning is a skill, and if you have it down good, you sure can do it to some pretty good accuracy too. For one, I think it'd be a great idea that a lot of people start using D/R as a primary means of naigation and then use the gps to back up your position every now and then. If you have one KNOWN position you can very accurately depict a track.

Especially within the continental US with it's abundance of naviagational beacons all over. And it doesn't make a lot of difference if you are going 160 knots or 480 knots, in fact I'll take the 480 knots since it'll be a little easier to calculate with.

It's a very bad thing to become solely reliable on the GPS unit, I've had quite a bit of RAIM errors when I was up the last time, and then the flight still has to be completed.

Back to the original post. Yes you can legally accept it, even with a handhelp GPS, as long as you have the necessary means of navigation to get yourself direct to that fix, heck I don't think that they'll frown upon you using a sextant to get yourself there. In the old days they flew over the ocean like that, and they also didn't have 5 extra hours worth of fuel with them to figure it out either.

Now the gps can't be your primary navigational instrument in this case, but it sure helps you to confirm your fix that you made by using all other means at your disposal

LOL, the sextant thing i posted at the same time as the previous pster, thought that was funny..

 

[KingAirer]

One VOR and a stopwatch works too. You don't need 2 VOR's, although it does make things easier.

I disagree. You cannot do that accurately. FOr example say your flying outbound from ABC VOR on the 123ºRadial. Lets say UGLLY instersection is 25 NM out from that VOR on that same radial. Without DME, or someother navaid that can define that INTX you cannot do it. Especially not a stopwatch. Yes you could approximate your position based on an estimated GS, but you cannot acurately define this INTX.

 

[Sctt@NJA]

Ok lets bring this back to a practical question:

If you were flying along direct to PODUNK intersection (hmm to many letters, oh well) via modern FMS and it sh!t the bed on you bringing you to /a equipment, would you.

A: Advise ATC and request vectors and/or airway type routing.

B: Advise ATC and keep trucking to PODUNK via VOR cross radial checks and DR or whatever.

C: Don't advise ATC and keep trucking to PODUNK and whatever other direct clearance they care to assign cause it easy, basic navigating .

 

[avbug]

Scott,

That is practical if you're already flying with the bells and whistles. If you have an FMS issue, then certainly advise the controller of your equipment failure (as you are required to do, and request what assistance you must. To answer your question, assuming your have experienced degraded nav capability AND it is the best choice under the circumstances, selection A: advise ATC and request alternate routing or vectors.

However, this has no bearing, nor part in the original question of the thread, which was as follows:

The other day, there I was, on an IFR flight plan to OSU (Don Scott Field) for the Ohio State Game. (Another subject all together) Level, 6000' about 12NM, east of the APE VOR heading to OSU. The controller calls me up and says Lance XXXXX proceed direct OSU. I do not have RNAV but I do have a non-IFR GPS. So, could I use the GPS and go direct? or continue to the VOR and fly the outbound heading for OSU?

Just so you are aware, at 6000' I was almost on top, in and out of the clouds. Bases were around 4500' so I did need to stay IFR to get down

The question was simple: could he use the GPS to go direct. Yes, he could, but not as a primary means of navigation. The question then followed, what are the legal ramifications. None. He could request a radar vector, but simply put, he's still legal so long as he is able to accurately fix his position.

As he was flying IFR on something other than RNAV, he had other means to accurately fix his position. We're not talking even a need to DR here, nor did anyone (least of all myself) suggest that he should. That was never the issue.

What did become an issue was those saying that without GPS or RNAV, it couldn't be done. Why, yes it can. In this case, he has GPS, albeit not approved. Regardless, it can still be done.

If he is using victor navigation and stays within the service volume, he can use that. Celestial nav is possible (don't know about you, but I do follow stars and constellations any time I can see them at night, sextant not withstanding). DR is a possibility. A combination of timing and electronic navigation is possible. The use of radar, vectors, and position fixing by that means is possible. Any combination of these is possible.

Further, the poster stated, as quoted above, that he could continue the flight outside IFR if necessary. There was no good reason why he couldn't continue the flight using his unapproved GPS, and could easily have been legal...either IFR or VFR.

My issue comes with those who are so small minded and who have let their personal skills deteriorate so far as to think that alternate means aren't possible, or aren't safe. That is simply false; it smacks of ignorance. So I ask again, just how do you think we did it before GPS?????????

 

[prpjt]

A little off topic, but I was just wondering how many times 'atpcliff' had to circle the globe on his trip from Texas to Detroit on that 135 degree heading. Now THAT's DR.

(We were at about 1500' MSL out of a S. TX airport (at about o'dark:30). The controller asked if we had an IFR or VFR box to go direct to Detroit. I told him we had NO box, whatsoever, but we could take a vector, direct when able.

THe controller cleared us, heading 135 degrees, direct Detroit when able-it's about 1100 miles or so. I had the maps out, and tracked our position via VORs as we went along. Every time we got a new controller, I told him we were on a vector, direct when able.)

Just kidding.

 

[Sctt@NJA]

I know perfectly well how the original scenerio works pre-GPS. Or non- rnav. You really think everyone here is a little kid?

First off the controller wouldn't have cleared him direct to an airport with no nav aide on it. He would have either flown an ATC vector to the field or he would have flown to the nearby VOR then outbound on a radial. Or he would have flown a vector to intercept a radial. Or he would have flown on published approach feeder routes.

 

[Sctt@NJA]

And really I know I should count to ten or something, but I need to say you are one pompous and arrogant guy. You write well though.

 

[avbug]

I know perfectly well how the original scenerio works pre-GPS. Or non- rnav. You really think everyone here is a little kid? First off the controller wouldn't have cleared him direct to an airport with no nav aide on it.

WRONG! Prior to GPS, one could, and often did, file from any point, to any point...and getting direct while doing it. That includes filing to a field or point without co-located navaid equipment. That's a fact, not arrogance.

Fact is, it can still be done today. An airplane really does fly when the radio quits, or when the FMS takes a siesta. It really does.

I guess we're all fortunate old Chris Columbus made it without GPS, else we'd still be sucking down cerveza and crumpets.

 

[Sctt@NJA]

Ok dude, what can I say. I have no doubt it used to be done that way. The oceans were crossed using the stars. The mail pilots used a series of light beacons on the ground. An instrument approach prior to gyros was done by doing a spin over the glow of city lights. (the spin being the only for-sure stable configuration preventing a spiral dive without a gyro instrument)

DC3 pilots would use a long trailing antenna for a primative "radar altimeter". And I am sure the list goes on and on of old practices that got the job done.

And in a way you may be right about limited experience. Mine only goes back about 15 years. And the early experience was all northeast. I can't speak for other times or places so I will take your word for it.

Talking here and now, (here being the good old USA and now being 2003) the kind of navigation you are talking about is obsolete. Sorry to break it to you.

See Snoopy58's post for example of how real to life modern pilots handle an ATC clearance direct sans area nav.

 

[avbug]

Look, mate; the question didn't revolve around that now, did it? (It did not). The poster, as restated in quotations above, asked about going direct when not equipped with all the golly-gee-whiz-bells-and-whistles avionics that you cannot live without.

The question was asked, and answered.

The marvel is the technofreaks who don't believe it can be done, legally and safely, without dual FMS, flight director, and a Papal blessing.

Nobody advocated making a regular practice out of flying IFR using strictly dead reckoning. Nor did anyone (myself included, if you'll be so kind as to check) suggest that "... some folks consider pilot DR an adequate substitute for an INS, and cross-tuning VOR's an adequate substitute for GPS or automatic DME/DME updates. Um, no, thanks! Not at 250+ knots!"

The airplane in question, applicable to the subject of this thread and the purpose of this discussion, DIDN'T HAVE INS, OR AN IFR APPROVED GPS, OR EQUIPMENT RECEIVING AUTOMATIC DME/DME UPDATES. You'll probably find that it isn't capable of 250 knots, either.

Accordingly, you have no arguement.

Out.

 

[bigD]

Yes you could approximate your position based on an estimated GS, but you cannot acurately define this INTX.

True, but I never said I'd get a GPS accurate answer. Of course the accuracy is pretty dependant on how well I can determine my ground speed, and of course how well I time the CDI movement, but it seems to me that in most cases, I can get a position fix that's within 5-10%, which for most distances within reception range of a VOR is only 2-5nm (at the altitudes that I fly, of course).

I'm not saying that I'd actually do this in an IFR environment, or that it's really practical in today's world (I've never flown a plane with only 1 VOR since my Cessna 150 days). I just said that it is possible to get a position with 1 VOR and a timer of some sort to time CDI movement.

 

[KingAirer]

I'm not saying that I'd actually do this in an IFR environment, or that it's really practical in today's world (I've never flown a plane with only 1 VOR since my Cessna 150 days). I just said that it is possible to get a position with 1 VOR and a timer of some sort to time CDI movement


Roger that, possible but certainly practical or smart in the real ifr world. You and i are in agreement on that.

 

[ksu_aviator]

One way of thinking that's not often presented, is simply getting from A to B without all the extra gear. If you're on the 180 radial of XYZ VOR, and want to get direct to a point on the 090 radial, it's not that hard. If you're 60 miles south, and want to go direct to a fix 30 miles east, it's simple. Without even having to do a lot of math, even.

I'm picking up what you are putting down here. Its all about simple geometry. But, in today's hi volume airspace, I doubt that ATC will consider this "reliable navigation." Just as an example, every time I go to PHL they will give me direct to Colin and if I stray even a little bit they will let me know. I can't dead reckon through that airspace, they have arrivals, restricted areas and tons of other traffic in the area.

I'm sure that back in the day of low volume and big skies, this would work beautifully, but the current airspace system just doesn't have that kind of tollerance for error.