Airways vs direct

dtuuri said:
Sorry you take it that way John. I'd rather you debate the issue than make it personal.

dtuuri
Click to expand...

Then why were you gratuitous and made it very personal, clearly stating I was not an operational type and then in a mean spirited way adding to your definition of the term "and sincerely makes an attempt to comply with rules and good operating practice".

I discussed the issue and we disagree. You made if personal and it was uncalled for and demands a public apology.
 
dtuuri said:
Insult you? If I ever did it was only to return the favor. As for John, it depends on what you mean by "stuff". He's an avionics guy and extremely knowledgeable technically, including RNAV TERPs requirements. He isn't an operational type and that's where we differ in our opinions. He doesn't see any problem with dumping Victor airways, but still retaining all the rules and procedures based on them. I do. Since he bowed out, how do you feel about it? Is 91.185 due for a rewrite to support the new point to point system without many airways?

dtuuri
Click to expand...

Victor airways, where necessary, will be replaced with T (low altitude) and Q (high altitude) routes.
 
midlifeflyer said:
I don't see where the 91.185 "route" - assigned, vectored, expected, filed - or altitude - highest of assigned, expected or regulatory minimum - require airways. Even the regulatory minimum contemplates non-published routes: the 1,000/2,000 AGL rule in 91.177(a)(2).
Click to expand...

Exactly. And as I noted above, the definition of OROCA gives us that off-route obstacle clearance, hence fulfilling the requirement in 91.177(a)(2) as MIA in that context.
 
Related to this thread, during the past three or so years, Class G airspace above 1,200, AGL, is disappearing in most of the Western U.S. More will disappear on November 18th. There will be a few areas remaining, but a small fraction of what existed three years ago.
 
aterpster said:
Related to this thread, during the past three or so years, Class G airspace above 1,200, AGL, is disappearing in most of the Western U.S. More will disappear on November 18th. There will be a few areas remaining, but a small fraction of what existed three years ago.
Click to expand...
Since radar coverage is nonexistant in most of these areas do they intend to provide surveilance with ADS-B?
 
midlifeflyer said:
91.185 has arguably been due for a reality check re-write ever since radar became more prevalent than position reporting.

But that aside, I don't see where the 91.185 "route" - assigned, vectored, expected, filed - or altitude - highest of assigned, expected or regulatory minimum - require airways. Even the regulatory minimum contemplates non-published routes: the 1,000/2,000 AGL rule in 91.177(a)(2).
Click to expand...

The rule supposes the pilot knows that the route complies with 91.177, easy enough to prove when you stay on airways or diligently plan off-airway segments, but under a point to point system ATC can clear an aircraft on a route that doesn't comply, thus making compliance with 91.185 impossible. What would be the highest MIA (within 4 nm of center) for each "route segment" on such an ad hoc clearance from any random point in space?

While trying in vain to turn up John Collins' resume (:)) I found it interesting that earlier this year he made an ATPAC proposal to have the FAA develop a tool for just the purpose I've been describing here (great minds think alike). But he withdrew it :(. I guess the FAA guys don't like good ideas when they see one and talked him out of the need.

dtuuri
 
Last edited:
John Collins said:
I discussed the issue and we disagree. You made if personal and it was uncalled for and demands a public apology.
Click to expand...
You bailed out, but welcome back. I haven't got a mean-spirited bone in my body. IIRC, you and I have enjoyed at least one rather long phone conversation and exchanged emails and supplied reference materials to each other pleasantly in the past. I've not changed. Nothing I've stated here was meant to offend. This is not an apology, just the facts.

dtuuri
 
John Collins said:
Since you were not at the meeting, you will have to guess why I withdrew it.
Click to expand...

Well, I did attend one meeting a long time ago. That was enough for me. I can't stand the pace of change (to coin a phrase), it's too frustratingly slow.

dtuuri
 
peerlesscowboy said:
Since radar coverage is nonexistant in most of these areas do they intend to provide surveilance with ADS-B?
Click to expand...

Beats me, John. I would expect so at some point in time.

I think the more immediate concern is being able to establish T routes. They are especially needed as the VORs go and there is no surveillance. Plus, unless all the airspace is controlled, they lose a lot of flexibility in designing T routes.
 
dtuuri said:
The rule supposes the pilot knows that the route complies with 91.177, easy enough to prove when you stay on airways or diligently plan off-airway segments, but under a point to point system ATC can clear an aircraft on a route that doesn't comply, thus making compliance with 91.185 impossible. What would be the highest MIA (within 4 nm of center) for each "route segment" on such an ad hoc clearance from any random point in space?
Click to expand...

==============================
(i) In the case of operations over an area designated as a mountainous area in part 95 of this chapter, an altitude of 2,000 feet above the highest obstacle within a horizontal distance of 4 nautical miles from the course to be flown; or
(ii) In any other case, an altitude of 1,000 feet above the highest obstacle within a horizontal distance of 4 nautical miles from the course to be flown.
==============================

OK, yeah. If you want to insist on a pin dance and treat each 1,000 or 2,000' AGL as a hard altitude, then you wind up with a theoretically different MIA every foot, so you constantly climb and descend and never level off,making compliance with the "higest" altitude impossible.

OTOH, if you don't want to do a pin dance, you use the OROCA and other cockpit tools for each quadrant as a number of others already said.

I prefer the no pin dance model.
 
midlifeflyer said:
==============================
(i) In the case of operations over an area designated as a mountainous area in part 95 of this chapter, an altitude of 2,000 feet above the highest obstacle within a horizontal distance of 4 nautical miles from the course to be flown; or
(ii) In any other case, an altitude of 1,000 feet above the highest obstacle within a horizontal distance of 4 nautical miles from the course to be flown.
==============================

OK, yeah. If you want to insist on a pin dance and treat each 1,000 or 2,000' AGL as a hard altitude, then you wind up with a theoretically different MIA every foot, so you constantly climb and descend and never level off,making compliance with the "higest" altitude impossible.
Click to expand...
Hey, it's not my rule that stipulates a pin dance as you put it. If I wrote the rules I'd tell ATC not to clear any aircraft "direct" until it reaches an altitude that satisfies all regulatory requirements all the way 'till the end of the route. Then I'd delete that responsibility from pilots in 91.177 and 91.185 on "direct flights".

midlifeflyer said:
...you use the OROCA and other cockpit tools for each quadrant as a number of others already said.
Click to expand...
Not if you follow the rules. OROCA is not MIA except in one highly special case. The rest of the time it's unnecessarily too high. But if you insist on that, then change 91.177 & 91.185 to state it. Why wouldn't you want to do that?

dtuuri
 
Interesting MORA/OROCA article by Jepps. The author has an amazingly apt surname. :)
 
midlifeflyer said:
==============================
(i) In the case of operations over an area designated as a mountainous area in part 95 of this chapter, an altitude of 2,000 feet above the highest obstacle within a horizontal distance of 4 nautical miles from the course to be flown; or
(ii) In any other case, an altitude of 1,000 feet above the highest obstacle within a horizontal distance of 4 nautical miles from the course to be flown.
==============================

OK, yeah. If you want to insist on a pin dance and treat each 1,000 or 2,000' AGL as a hard altitude, then you wind up with a theoretically different MIA every foot, so you constantly climb and descend and never level off,making compliance with the "higest" altitude impossible.
Click to expand...

You've lost me. The off-route altitude requirements of 91.177 are minimum altitudes, not mandatory altitudes.
 
midlifeflyer said:
==============================
(i) In the case of operations over an area designated as a mountainous area in part 95 of this chapter, an altitude of 2,000 feet above the highest obstacle within a horizontal distance of 4 nautical miles from the course to be flown; or
(ii) In any other case, an altitude of 1,000 feet above the highest obstacle within a horizontal distance of 4 nautical miles from the course to be flown.
==============================

OK, yeah. If you want to insist on a pin dance and treat each 1,000 or 2,000' AGL as a hard altitude, then you wind up with a theoretically different MIA every foot, so you constantly climb and descend and never level off,making compliance with the "higest" altitude impossible.
Click to expand...
FWIW,,,,I interpret FAR 91.177(a)(2) as refering to the the whole "...course to be flown" between each described fix, IOW if I'm flying GGW --D-> 15MT (045* radial, 33 nm) the relevant obstacle is a communications tower about halfway out the elevation of which controls the MIA for the whole route. If I wanted lower after passing 4 nm northeast of that tower I'd need to have that fix in my clearance. Is that not the accepted interpretation?
 
midlifeflyer said:
...............
OTOH, if you don't want to do a pin dance, you use the OROCA and other cockpit tools for each quadrant as a number of others already said.
Click to expand...
Unless you're route happens to pass within 4 nm of the highest obstacle in the quadrant OROCA is irrelevant chart clutter.
That leaves us with "other cockpit tools" (Garmin terrain database?) to determine MIA. Interesting concept, ...... no need for preflight planning, just take a cruise clearance and don't let the screen turn red :happydance:
 
Last edited:
It's a little tough to argue that flatland victor airways can't be eliminated inside the current rules, since that has already happened several years ago, for all practical purposes.
 
JHW said:
It's a little tough to argue that flatland victor airways can't be eliminated inside the current rules, since that has already happened several years ago, for all practical purposes.
Click to expand...

Nonetheless, they still serve the same fundamental purpose. In the event of a radar failure or heavy traffic they provide non-radar "rails" and known non-radar separation between some, but not all adjacent airways,

T routes will provide the same type of tool for ATC.
 
JHW said:
It's a little tough to argue that flatland victor airways can't be eliminated inside the current rules, since that has already happened several years ago, for all practical purposes.
Click to expand...

So should I just stop filing them?
 
peerlesscowboy said:
FWIW,,,,I interpret FAR 91.177(a)(2) as refering to the the whole "...course to be flown" between each described fix, IOW if I'm flying GGW --D-> 15MT (045* radial, 33 nm) the relevant obstacle is a communications tower about halfway out the elevation of which controls the MIA for the whole route. If I wanted lower after passing 4 nm northeast of that tower I'd need to have that fix in my clearance. Is that not the accepted interpretation?
Click to expand...

I agree with you. Just joining in the pin dance.
 
ChrisK said:
So should I just stop filing them?
Click to expand...
Absolutely not. I've been looking for an old sectional and finally found one with the old tower on it. You might have filed direct Lorain County (EDIT: LPR) from CMH (Columbus) and received vectors after takeoff and then a clearance something like, "Procede direct Appleton (APE) direct Lorain County, maintain 3000 feet." Then before being handed off you could have gone NORDO. Your original route would have met 91.177 and missed the tower (2916' MSL) by more than 4 nm, but the revised clearance would put you smack over it. Columbus doesn't know the tower exists (no tools) and you figure 3000' is ok, after all it was assigned and your "go" decision was based on flying at 3000' to stay below the freezing level. Boom, you'll hit the tower. :(

Only plan or accept direct routes you know are safe because you have enough altitude no matter how far off the beaten path they lead you. You filed the right way, it only added two minutes to your flight, but gives you a lot of piece of mind.

dtuuri
 
Last edited:
dtuuri said:
Absolutely not. I've been looking for an old sectional and finally found one with the old tower on it. You might have filed direct Lorain County (LRP) from CMH (Columbus) and received vectors after takeoff and then a clearance something like, "Procede direct Appleton (APE) direct Lorain County, maintain 3000 feet." Then before being handed off you could have gone NORDO. Your original route would have met 91.177 and missed the tower (2916' MSL) by more than 4 nm, but the revised clearance would put you smack over it. Columbus doesn't know the tower exists (no tools) and you figure 3000' is ok, after all it was assigned and your "go" decision was based on flying at 3000' to stay below the freezing level. Boom, you'll hit the tower. :(

Only plan or accept direct routes you know are safe because you have enough altitude no matter how far off the beaten path they lead you. You filed the right way, it only added two minutes to your flight, but gives you a lot of piece of mind.
Click to expand...

I wouldn't plan or fly off-route below the OROCA except under positive radar control (or during an IAP). In this case the OROCA is 3,200', so it would miss that tower (though not by much).
I would also not launch IMC without an up-to-date moving map showing terrain and obstacles, which is fairly inexpensive protection nowadays (at least the non-certified version).
 
RotorDude said:
I wouldn't plan or fly off-route below the OROCA except under positive radar control (or during an IAP). In this case the OROCA is 3,200', so it would miss that tower (though not by much).
Click to expand...
This is a hypothetical, since the tower doesn't really exist today. If it did, the OROCA would be, say, 4200' instead. That would leave a lot of good flyable routes within the tic marks beyond your reach. Anything more than 4 nm from the site would be off-limits by your SOP.

RotorDude said:
I would also not launch IMC without an up-to-date moving map showing terrain and obstacles, which is fairly inexpensive protection nowadays (at least the non-certified version).
Click to expand...
If that's what you believe it takes to be safe then it begs the question of whether the equipment should be mandatory. Hand-helds are just cargo, a box of PCBs in the eyes of the FAA, so that would mean TSO'd installed equipment as a minimum. Do we want that?

dtuuri
 
Last edited:
RotorDude said:
I wouldn't plan or fly off-route below the OROCA except under positive radar control (or during an IAP). In this case the OROCA is 3,200', so it would miss that tower (though not by much).
I would also not launch IMC without an up-to-date moving map showing terrain and obstacles, which is fairly inexpensive protection nowadays (at least the non-certified version).
Click to expand...

Since the tower is no longer there, the 3200 OROCA would clear all terrain and obstacles by 200 feet more than the 1050 feet clearance provided at 3000 feet according to the ForeFlight profile view set to a +/- 4 NM either side of the random route. ForeFlight uses the Digital Obstacle File that the FAA provides and maintains as a publicly available database for all known obstacles over 200 feet AGL. OTOH, if the tower was still there, the OROCA would be at least 4000 feet when rounded up to the next 100 feet.

I asked an FAA contact (he is responsible for developing controller guidance at HQ and a high experience ex TRACON controller) what would be expected by a controller in a lost com situation, the aircraft was on a random route, the OROCA was higher than the assigned or expected altitude. He agreed the OROCA would apply.
 
dtuuri said:
This is a hypothetical, since the tower doesn't really exist today. If it did, the OROCA would be, say, 4200' instead. That would leave a lot of good flyable routes within the tic marks beyond your reach. Anything more than 4 nm from the site would be off-limits by your SOP.
Click to expand...

I guess we'd have to differ on what is "good", which is clearly subjective. I don't see a problem in using the (higher, coarser but safer) OROCA if I don't have a way to delineate the bare minimum +/- 4 nm corridor around my route.

dtuuri said:
If that's what you believe it takes to be safe then it begs the question of whether the equipment should be mandatory. Hand-helds are just cargo, a box of PCBs in the eyes of the FAA, so that would mean TSO'd installed equipment as a minimum. Do we want that?
Click to expand...

No, we don't, and I am not suggesting that. My own pre-launch requirements are higher than the bare minimums prescribed by law, which in this case would be to use the OROCA, available to everyone.
 
John Collins said:
................
I asked an FAA contact (he is responsible for developing controller guidance at HQ and a high experience ex TRACON controller) what would be expected by a controller in a lost com situation, the aircraft was on a random route, the OROCA was higher than the assigned or expected altitude. He agreed the OROCA would apply.
Click to expand...
Is this official FAA policy, and if so why isn't it regulatory?
 
RotorDude said:
.............................. My own pre-launch requirements are higher than the bare minimums prescribed by law, which in this case would be to use the OROCA, available to everyone.
Click to expand...
And what if OROCA is above 12,500' msl and you don't have oxygen onboard?
 
peerlesscowboy said:
And what if OROCA is above 12,500' msl and you don't have oxygen onboard?
Click to expand...

I would suggest that if you know you'll be flying over such terrain where clearing the OROCA if you go NORDO off-airway is a concern, you'll either need to have oxygen, or dispense with off-airway routing.
 
I'd like to see more T-routes out here in the west designed to make MEAs as low as possible. This would help a lot with oxygen and icing concerns.

You can design a T-route to thread a mountain pass much more easily when you are not restricted by ground-based navaid placement.
 
peerlesscowboy said:
And what if OROCA is above 12,500' msl and you don't have oxygen onboard?
Click to expand...
Or... what if someone above is cruising down an intersecting airway at MEA? What if he went NORDO at the exact same time (darned ground hogs)? Is he supposed to zoom up to OROCA too?

dtuuri
 
RotorDude said:
I would suggest that if you know you'll be flying over such terrain where clearing the OROCA if you go NORDO off-airway is a concern, you'll either need to have oxygen, or dispense with off-airway routing.
Click to expand...
It's a Looooooong way from Cutbank to Kalispell via the airways.
 
You must log in or register to reply here.
Back
Top