Cleared Direct Destination?

[KingAirer]

I think SCtt@NJ and I are thinking along the same lines. To be able to deterimine your position accurately using traditional means, other than seeing the ground, your going to need two of someting. Two VORs, VOR and NDB, VOR/DME etc... Are you sure that if you take this direct route you will have acceptable nav aids along the route? If youve done your homework ahead of time, maybe. But even then You are going to have your hands full trying to draw a stright line from point a to B with off route VORs.
You are correct that if you can determine your position then you would be legal. However, can you really be assured that you are on course at all times and on the straight line between your starting and ending point?

Good discussion guys.

 

[bigD]

Avbug, are you a ghost? Because you sound EXACTLY like my late grandfather.

When I was a student pilot, I remember sitting in my grandparents' living room reading about navigation via VOR. Gramps sat down next to me, took out a piece of paper, and drew a top down view of an airplane, an airport some distance away, and a VOR somewhere as well (but not directly between the airplane and airport).

He asked me, "Okay, tell me how you'd get to the airport if there were no landmarks on the ground to guide you." So I took a ruler and found the radial off the VOR for the airport, then told Gramps that I'd fly to the VOR, and then fly the radial from the VOR until I'm over the airport.

Now I don't remember the exact rant I received (it was 10 years ago), but Avbug's response certainly caused some deja vu! Lots of use of the words "you kids", "in my day", and something about being able to do this "all while being shot at by the Japs".

Anyway, he didn't give me the answer, but instead insisted that I stay in the living room for however long it took me to figure out how to get there in a straight line.

Heh. D*mn I miss him.

 

[avbug]

I am your grandfather. Sit up straight when I'm talking to you. In my day we didn't have computers and didn't need them. We used pen knives and carved in the palms of ourhands. And we were grateful. Sometimes we didn't have pen knives, we used broken glass, and I can tell you we were lucky to have glass. Used to be sod, instead. And we didn't have palms most of the time, because they were too scarred and bloody from working in the field. We had to scribble on goats hooves, and we were grateful for the goats. In fact, I loved those goats. Too often, some said, but I really loved those goats...

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.

Sixty is twice as far south, as you want to go east. Pick a point on your VOR navhead that's a thumb width down from the middle part of the instrument. Set your heading in the OBS. Now pick a point that's half a thumb width to the right of the center of the instrument. Now draw a line between them. Now draw a line parallel to that, which intersects the middle of the instrument.

The number over which that line passes on the upper right hand portion of the OBS dial will be the heading to which you must turn to go direct. Problem solved.

Now wind may affect that a bit, but you can account for wind very quickly, especially when making a series of such calculations as you move along. Just like DR navigation, updating fixes continuously means that your nav should get more and more precise as you fly...and yes, you can get there from here.

If you can draw a line on a chart, and then determine that you're staying on that line by running constant checks and then making the requisite corrections, you've met the requirements of the regulation. You're running a safe ship, and it's been done for a long time.

And yes, I'm grateful.

 

[Sctt@NJA]

Ok Avbug, you go ahead and do that when you are cleared direct to white intersection coming out on the Teterboro Five departure with no rnav or gps. Ya right. Lets get real shall we?

 

[StarChecker]

I flew the TEB 5 every night for over a year, single-pilot and was cleared direct everywhere, often with two VOR's and a DME. Get your chart out, pick a heading, and wait to get yelled at. Otherwise....you're doing fine.

 

[atpcliff]

Hi!

This is easy.

You tell the controller you have a VFR GPS, and you need a vector heading direct when able.

The controller tells you, fly heading 235 degrees, direct DQN when able. You are legally flying IFR under a controller's direction, until you can receive DQN with your VOR. If you want, when you switch to a new controller, you can ask for a new heading direct.

I had a similar situation a while back. I was flying a plane WITHOUT a GPS, IFR or VFR, and we didn't have a handheld either (this was a Wright Model B that we leased-hahaha!).

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.

Sometimes flying a night is great!

Cliff
SDF

 

[rettofly]

To be able to deterimine your position accurately using traditional means, other than seeing the ground, your going to need two of someting. Two VORs, VOR and NDB, VOR/DME etc...QUOTE]

Really! I guess my instrument rating doesn't count, since the Cherokee 140 I used for the check ride had only ONE VOR and no ADF. The DPE had me pretty busy doing an intersection hold using only the ONE VOR on board.
BTW: This was a loooong time ago, and I have since learned to cope with using multiple navaids, even GPS and FMS.

 

[ibaflyer]

well..... thanks for the information. I have enjoyed reading all of your comments. I guess I kind of did the right thing according to some of you.

I just looked at the old low alt. chart, looked at the APE VOR and picked a heading the I thought would get me there.

I NEVER EVER..thought of looking at the GPS to give me a hand with the heading. That may have been illegal

Thanks again for all of the information.

 

[KingAirer]

To be able to deterimine your position accurately using traditional means, other than seeing the ground, your going to need two of someting. Two VORs, VOR and NDB, VOR/DME etc...QUOTE]

Really! I guess my instrument rating doesn't count, since the Cherokee 140 I used for the check ride had only ONE VOR and no ADF. The DPE had me pretty busy doing an intersection hold using only the ONE VOR on board.
BTW: This was a loooong time ago, and I have since learned to cope with using multiple navaids, even GPS and FMS.

Just curious how you defined the intersection with only one vor? Also, note that all the things i listed are navaids and not aircraft instruments.

 

[Vladimir Lenin]

Just curious how you defined the intersection with only one vor? Also, note that all the things i listed are navaids and not aircraft instruments.

alternate the navaid freqs and bearings??? it's time consuming and not the most accurate, but there's nothing in the FARs that says you have to have two VOR receivers

 

[KingAirer]

AHHHH...neither did I!

Look im saying you must be picking up 2 VORs. or 2 of something to triangulate or define your position.

 

[bigD]

Look im saying you must be picking up 2 VORs. or 2 of something to triangulate or define your position.

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

 

[Vladimir Lenin]

AHHHH...neither did I!

Look im saying you must be picking up 2 VORs. or 2 of something to triangulate or define your position.

yea, but not necessarily at the same time

and for avbug, if everyone could navigate by dead reckoning while in clouds, we wouldn't need IFR navigation. Granted, with equip failure, it's the only way, otherwise it's just stupid. I don't know where you fly and what you fly, or whether you fly at all (having read some of your rants), but asking for a vector or declining "direct" would be the safest thing to do, IMHO

 

[Sctt@NJA]

"I flew the TEB 5 every night for over a year, single-pilot and was cleared direct everywhere, often with two VOR's and a DME. Get your chart out, pick a heading, and wait to get yelled at. Otherwise....you're doing fine."

Or you could save yourself a potential violation and remind them of your equipment type.

ATC makes mistakes. And nowadays they often assume everyone has some sort of area navigation. If you are cleared direct to some interesection and you wandered off course and they asked you what you were doing and you told them you only have 2 VORs and a DME they would say "Why didn't you say so? Fly heading XXX cleared direct XXX VOR when able"

Using Vors to do mental Rnav calculations for direct navigation (to someplace other than to or from a vor) is an oddball procedure that simply isn't necessary. Or expected by ATC. Or accurate. Or smart. By god especially if you are flying in amongst mountains. Heck they went to alot of effort to create airways that are reliable to navigate, have garaunteed radio coverage and terrain clearance ect. Why on earth would you throw that protection away?

Now all this being said, I have certainly flown direct without Rnav or gps. I have done it on small scales like the 30 miles or so between EWB and OWD where there is an ndb at OWD but you don't pick it up till about 10 miles out. Just flew a 350 heading till the NDB comes in. I have also flown from the Carolinas to the Northeast at night that way in a Cheyenne using a method like Avbug described. But we were well above any mountains and we weren't in a busy terminal area where tolerances are tight.

But really in the EWB to OWD case I should have asked for a vector and in the second case should have flown the airways, or taken a vector for direct when able to someplace up the road.

This is accepted, normal, pilot procedure stuff and I am fairly amazed at some of the opinions here

 

[Snoopy58]

Sctt@NJA,

I'll join you in amazement at some of the rants.

"XXX123, you're cleared direct PARKS"
"ah, sorry, we're slant alpha tonight"
"my bad, fly heading 080 & join the 12R localizer"

Is it POSSIBLE to fly a fix-to-fix accurately? Yeah, we did it all the time in the T-38. Is it a clever idea in a busy terminal area? Absolutely not. As winds change in the descent, you can either spend ALL your time continuously updating your track, or else you may end up flying a pretty curvy path "direct" to said fix.

As for drawing on my charts, that works a lot better when the charts don't have to last for several dozen flights in the same area before they get replaced.

In my small segment of the -121 world, we don't fly fix-to-fix in /A jets. It isn't considered a legal clearance, and I've NEVER had ATC take offence at us turning one down.

Like I said, I was pretty surprised at some of the posts here. Looks like 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!

Snoopy