7600 Descent

[Captain]

My plane has 2 VHF and a Sat Phone.

But the topic is 'Lost Comms' so that implies all comms, whatever that may be, don't work. Do most planes that can hit 390 have redundant systems? Sure. Its less likely maybe but the rules and procedures don't have exceptions carved out for that as far as I know.

So, put yourself in a CJ1 or P180 at 390 with a solid layer below you. TAF had your destination at mins and your alternate is 1,000' overcast. Comms are out...all. What do you do and why.

Hitting the IAF at 390 is VASTLY different than hitting it at MEA, and in real life you have to pick one course of action. What do you do?

 

[Jaybird180]

My plane has 2 VHF and a Sat Phone.

But the topic is 'Lost Comms' so that implies all comms, whatever that may be, don't work. Do most planes that can hit 390 have redundant systems? Sure. Its less likely maybe but the rules and procedures don't have exceptions carved out for that as far as I know.

So, put yourself in a CJ1 or P180 at 390 with a solid layer below you. TAF had your destination at mins and your alternate is 1,000' overcast. Comms are out...all. What do you do and why.

Hitting the IAF at 390 is VASTLY different than hitting it at MEA, and in real life you have to pick one course of action. What do you do?

Can you flesh this out with a more descriptive example? But I don't see a way around 91.185, the question as I understand is HOW to comply with it in a safe manner. In many cases there just isn't time to continue the approach from FL390 at the IAF, so where do you go? As Ed said in post #6, it's not practical to circle down over the fix either.

Need more info. Have a destination in mind for this scenario? Also is the closest VMC airport in range?

 

[dtuuri]

You don't always get a hold when your clearance limit is changed (as Steven said), and often the route isn't mine...it assigned so the last fix being an IAF or having a feeder isn't 'assumed'.

You have not thought of an example of that yet? Maybe because it isn't true? From the controller's handbook, my emphasis:

4-2-5. ROUTE OR ALTITUDE AMENDMENTS

a. Amend route of flight in a previously issued clearance by one of the following:

1. State which portion of the route is being amended and then state the amendment.

PHRASEOLOGY-
CHANGE (portion of route) TO READ (new portion of route).

2. State the amendment to the route and then state that the rest of the route is unchanged.

PHRASEOLOGY-
(Amendment to route), REST OF ROUTE UNCHANGED.

3. Issue a clearance “direct” to a point on the previously issued route.

PHRASEOLOGY-
CLEARED DIRECT (fix, waypoint).

Or

CLEARED DIRECT (destination) AIRPORT.

NOTE-
Clearances authorizing “direct” to a point on a previously issued route do not require the phrase “rest of route unchanged.” However, it must be understood where the previously cleared route is resumed. When necessary, “rest of route unchanged” may be used to clarify routing.​

Shame on any pilot who accepts a clearance to the Twilight Zone with no further routing.

As for not getting an EFC, no problem. That's covered in 91.185--you simply don't hold without one. Wouldn't make sense to hold without knowing when to leave, would it?

As for being at FL 390 or 410 or 450, etc., until over the IAF being "silly" and "crazy", well that's the rule and I'm happy with it. It would be crazy to start down at 125 NM or 100 NM or 75 NM or whatever, slicing through multiple jet routes and airways as you careen toward your destination on some vertical lark of your own. Nobody can guess what your whim might be or which airliner stuffed with people you might jeopardize. That flight path is the crazy one.

Having all those backup options, phones, email and the like makes me laugh. It reminds me of the golfer who bought balls that float. Thought he'd lose less of 'em in the ponds along the fairway. His perspective changed when he realized to be useful he would also have needed to buy a boat. Here's a perspective-changing article for the equipment addicts:

http://www.apnewsarchive.com/1991/B...Shutdowns/id-41ea3dec4ad1942150ff99c7d6675e02​

dtuuri

 

[dtuuri]

... the question as I understand is HOW to comply with it in a safe manner. In many cases there just isn't time to continue the approach from FL390 at the IAF, so where do you go? As Ed said in post #6, it's not practical to circle down over the fix either.

Not "time" to continue the approach? Not "practical"?

Above 14,000' each lap in a holding pattern is five minutes, so at 3,000 fpm you can lose 15,000' per lap. From FL 450, it takes two laps to get to 15,000'. Say it's 2000' fpm and four minutes per lap from there on down. Another two laps at most? Of course, you're at flight idle, so fuel burn is less than taxiing on the ground--and you saved time en route by staying at altitude where true airspeed is higher. Maybe saved some fuel too.

dtuuri

 

[John Collins]

Look, I don't know the answer here. I'm asking the question. Am I the only one who thinks flying over the IAF at FL390 seems silly?

I am sure you are not the only one who thinks flying over the IAF at FL390 seems silly. However, that is the regulation. How would you change the regulation? I suspect that the change would result in its own silly scenarios and it might even be more confusing and dangerous. You may not think that this subject has gotten much thought and discussion by very knowledgable folk as the rule has evolved, but it has.

 

[roncachamp]

I am sure you are not the only one who thinks flying over the IAF at FL390 seems silly. However, that is the regulation. How would you change the regulation? I suspect that the change would result in its own silly scenarios and it might even be more confusing and dangerous. You may not think that this subject has gotten much thought and discussion by very knowledgable folk as the rule has evolved, but it has.

The regulation doesn't mention the IAF, it refers to the clearance limit. When the clearance limit is an IAF the altitude assigned is likely much lower than FL390.

 

[dtuuri]

The regulation doesn't mention the IAF, it refers to the clearance limit. When the clearance limit is an IAF the altitude assigned is likely much lower than FL390.

John's referring to the case when holding at a clearance limit is not applicable: "Cleared to (destination airport) via...". Then, until reaching the IAF, 91.185(c)(2)(i)(ii)&(iii) apply (altitude per route segment).

Good point on holding instruction altitude assignments for a clearance limit at the IAF though.

dtuuri

 

[Dr. O]

Well Fat Albert can't quite reach the flight levels but 8 to 12 thousand is pretty normal for IMC flight for us. And we do have 3 coms but losing all three is certainly probable with just one battery. Do have 2 generators, but hey, a shorted battery will drop both of them off line.
Let me hasten to say I am just Joe Pilot, not a hot shot ATP/CFII/Controller, or even a flight attendant.
Now, what would I do suddenly if NORDO in IMC because the battery exploded - and likely they will be getting only primary returns from me with a shorted out electrical system so no Mode C?

Well, (had to think about it for 30 seconds) I agree that following the clearance is generally agreed upon - and required in the regs - is best.
So, that leaves me approaching my clearance destination at a rather high altitude that ATC would have been stepping me down from. But given that I don't know where that would have occurred or what altitudes or vectors I would have been assigned, I'm betting the controllers will like me to stay as cleared and motor my way to the final destination following ye old clearance.
So in thinking it through I agree with the official rule - follow the altitudes and route you were cleared for and get close to the initial approach fix for the landing.

At this point I am not worried about hitting another plane (big sky) knowing that ATC will clear a bubble of space around me. Once I am over some point/fix on the approach plate where I am guaranteed obstruction clearance I would either circle down, or use a holding pattern descent if one is handy.
Then go find my IAP, execute any PT as published and shoot the approach.

In my case I will likely be on my VFR moving map on battery power. I can count on it working for one hour under any and all conditions, and likely much longer if I turn it off and on to stretch the battery. But that will the deciding factor to determine if I follow the clearance all the way to the end or not.. If it appears that I will not have battery power to reach the end of the clearance, then I will be forced to divert to the nearst suitable airport before I lose my only source of navigation in IMC.

 

[Jaybird180]

Here's a perspective-changing article for the equipment addicts:

http://www.apnewsarchive.com/1991/B...Shutdowns/id-41ea3dec4ad1942150ff99c7d6675e02​

dtuuri

Yum...technology is good.

Same as I believed before reading the article

 

[MarkZ]

As for being at FL 390 or 410 or 450, etc., until over the IAF being "silly" and "crazy", well that's the rule and I'm happy with it. It would be crazy to start down at 125 NM or 100 NM or 75 NM or whatever, slicing through multiple jet routes and airways as you careen toward your destination on some vertical lark of your own. Nobody can guess what your whim might be or which airliner stuffed with people you might jeopardize. That flight path is the crazy one.

dtuuri

Not only is that flight path crazy, but in this post-9/11 world, you can bet it will get you intercepted by some fighters should it take you anywhere near any cities/power plants/military installations/etc.

Again, ATC expects you to follow the book. No matter how silly it sounds. Initiate a safe hold at your clearance limit, and if your clearance limit is not an IAF, begin an approach at the IAF when safe to do so. Anything else you do with the airplane is contrary to the FAR's and will most likely be a violation.

Now, having said all that, ATC is still treating you as an emergency. We can't talk to you, we are not sure what you will do. Because of that, we close the airport at an appropriate time (it's happened at ORD before), and we block the airspace ahead and below you. Just. In. Case.

 

[dtuuri]

Once I am over some point/fix on the approach plate where I am guaranteed obstruction clearance I would either circle down, or use a holding pattern descent if one is handy.

I'd say you've got the big picture, Doc. If holding is required by the IAP, TERPS wants it charted at the IAF or at least have the IAF within the holding pattern on the inbound course. Keeping in mind that the initial segment, feeder routes and Victor airways are all eight miles wide, holding at an IAF while descending gives you real good odds even if there isn't a pattern there. Just keep your speed down (tighter turn radius).

dtuuri

 

[NoHeat]

To further muddy things up, let's toss in what the AIM has to say:

6-4-1. Two‐way Radio Communications Failure

a. It is virtually impossible to provide regulations and procedures applicable to all possible situations associated with two‐way radio communications failure. During two‐way radio communications failure, when confronted by a situation not covered in the regulation, pilots are expected to exercise good judgment in whatever action they elect to take. Should the situation so dictate they should not be reluctant to use the emergency action contained in 14 CFR Section 91.3(b).​

It seems to me, though, that this situation is covered by the regulation, albeit in a silly way (you stay at FL390 till you're over the airport, then you descend to an IAF). So the bolded "get-of-jail card" text doesn't look like it would help in this case. What does everyone else think?

 

[Palmpilot]

...But I don't see a way around 91.185, the question as I understand is HOW to comply with it in a safe manner. In many cases there just isn't time to continue the approach from FL390 at the IAF, so where do you go? As Ed said in post #6, it's not practical to circle down over the fix either...

Since those are questions that are not covered by the regulation, I would say that the following excerpt from AIM 6-4-1 would apply:

During two-way radio communications failure, when confronted by a situation not covered in the regulation, pilots are expected to exercise good judgment in whatever action they elect to take. Should the situation so dictate they should not be reluctant to use the emergency action contained in 14 CFR Section 91.3(b).​

It goes on to say

Whether two-way communications failure constitutes an emergency depends on the circumstances, and in any event, it is a determination made by the pilot.​

According to the Pilot/Controller Glossary, it doesn't have to be a distress condition to be an emergency. A potential distress condition is enough, and I would say that there is a potential for distress conditions to be created by remaining in the IFR system for the extra time required to descend from FL390 when the pilot could have been doing it at the normal times, and by having to essentially invent a procedure for getting down from an abnormal location.

Especially in a radar environment, I would say that a procedure that allows a normal descent profile, following published routes, is the safest course of action.

And of course, all of the above assumes that if the aircraft is in VFR conditions, the pilot does not know of a suitable airport within fuel range where it would be possible to remain in VFR conditions for descent and landing.

 

[Palmpilot]

To further muddy things up, let's toss in what the AIM has to say:

6-4-1. Two‐way Radio Communications Failure

a. It is virtually impossible to provide regulations and procedures applicable to all possible situations associated with two‐way radio communications failure. During two‐way radio communications failure, when confronted by a situation not covered in the regulation, pilots are expected to exercise good judgment in whatever action they elect to take. Should the situation so dictate they should not be reluctant to use the emergency action contained in 14 CFR Section 91.3(b).​

It seems to me, though, that this situation is covered by the regulation, albeit in a silly way (you stay at FL390 till you're over the airport, then you descend to an IAF). So the bolded "get-of-jail card" text doesn't look like it would help in this case. What does everyone else think?

An emergency is a distress or urgency condition. I think doing things in a silly way creates a potential distress condition (= urgency) at minimum.

I also think that the regulation is so badly written that any lost comm where a VFR descent and landing is not possible could be considered an emergency on that basis alone.

 

[Captain]

You have not thought of an example of that yet? Maybe because it isn't true?

What example? What isn't true? Are you just trying to wind me up?


From the controller's handbook, my emphasis:

4-2-5. ROUTE OR ALTITUDE AMENDMENTS

a. Amend route of flight in a previously issued clearance by one of the following:

1. State which portion of the route is being amended and then state the amendment.

PHRASEOLOGY-
CHANGE (portion of route) TO READ (new portion of route).

2. State the amendment to the route and then state that the rest of the route is unchanged.

PHRASEOLOGY-
(Amendment to route), REST OF ROUTE UNCHANGED.

3. Issue a clearance “direct” to a point on the previously issued route.

PHRASEOLOGY-
CLEARED DIRECT (fix, waypoint).

Or

CLEARED DIRECT (destination) AIRPORT.

NOTE-
Clearances authorizing “direct” to a point on a previously issued route do not require the phrase “rest of route unchanged.” However, it must be understood where the previously cleared route is resumed. When necessary, “rest of route unchanged” may be used to clarify routing.​

Shame on any pilot who accepts a clearance to the Twilight Zone with no further routing.

As for not getting an EFC, no problem. That's covered in 91.185--you simply don't hold without one. Wouldn't make sense to hold without knowing when to leave, would it?

As for being at FL 390 or 410 or 450, etc., until over the IAF being "silly" and "crazy", well that's the rule and I'm happy with it. It would be crazy to start down at 125 NM or 100 NM or 75 NM or whatever, slicing through multiple jet routes and airways as you careen toward your destination on some vertical lark of your own. Nobody can guess what your whim might be or which airliner stuffed with people you might jeopardize. That flight path is the crazy one.

So a chop and drop over the field is less crazy than a nice stable descent from a normal let down point? Okay...

Having all those backup options, phones, email and the like makes me laugh.

I listed my equipment and it's comparable to any GA plane. I don't have email and whatever causes two VHF radios to crap out is probably going to crap out the Sat Phone assuming it isn't differed anyway. Besides, none of this is likely, it's an academic discussion.

It reminds me of the golfer who bought balls that float. Thought he'd lose less of 'em in the ponds along the fairway. His perspective changed when he realized to be useful he would also have needed to buy a boat. Here's a perspective-changing article for the equipment addicts:

http://www.apnewsarchive.com/1991/B...Shutdowns/id-41ea3dec4ad1942150ff99c7d6675e02​

dtuuri

Super post not moving the conversation anywhere.

 

[John Collins]

Many of you say it is silly, so what is the alternative to the "silly" rule. What is the non silly rule. What is really silly if you can't come up with a rule that can stand up to criticism.

 

[Captain]

I would guess a large percentage of the time I get a route it ends with a VOR or fix thats not an IAF and then DIRECT to the field.

Also, the possibility of landing VMC is not a part of this discussion since we ALL agree what to do there.

 

[roncachamp]

Many of you say it is silly, so what is the alternative to the "silly" rule. What is the non silly rule. What is really silly if you can't come up with a rule that can stand up to criticism.

I think the whole scenario is silly. A loss of all communications capability yet there's no loss of any other avionics?

 

[Captain]

I think the whole scenario is silly. A loss of all communications capability yet there's no loss of any other avionics?

Isn't that the premise of the lost comms scenario regardless of plane?

 

[dtuuri]

You don't always get a hold when your clearance limit is changed (as Steven said), and often the route isn't mine...it assigned so the last fix being an IAF or having a feeder isn't 'assumed'.

Can you give an example of how that would be a problem if you were trying to follow 91.185?

What example? What isn't true? Are you just trying to wind me up?

Naw, you said you didn't know, so I'm just trying to enlighten you.

As for your comment that it would be a "chop and drop", well you don't have to scare any passengers on my or the FAA's account. I was just doing a little math to show that being up there in the flight levels isn't quite to the dark side of the moon. Actually, at flight idle and following AFM procedures, 14,000' is only three minutes away from the highest certified operating altitude by law.

My other comment about email, etc., was for the gadget freaks--if the shoe fits only. Some folks like a lot of needless gadgetry, but don't necessarily rely on it. Others would fly a plane into a hillside while fooling around with it.

I still think ATC is the weak link most likely to invoke 91.185. Backhoes and beavers. Airplane problems that big might dictate emergency authority first.

dtuuri

 

[Palmpilot]

Many of you say it is silly, so what is the alternative to the "silly" rule. What is the non silly rule. What is really silly if you can't come up with a rule that can stand up to criticism.

I think it would be difficult to come up with a rule that stood up to criticism worse than the existing one!

Here is what I would do:

The first word of 91.185(c)(2) is "Altitude." I would replace that with "Cruising altitude." That allows pilots some flexibility in deciding when to start their descent when nearing the destination.

If that's too much flexibility for some, then I would add a section specifying that descent below the cruising altitude should begin at a time that allows normal rates of descent, but not before joining a published route at or above the published altitude.

And while I was at it, I would rewrite section (c)(3) to specify that, in the absence of specific holding instructions from ATC, holding is not required when the clearance limit is the destination airport.

 

[Palmpilot]

I think the whole scenario is silly. A loss of all communications capability yet there's no loss of any other avionics?

An audio panel failure would do it. So would simultaneous failure of both the headset and the loudspeaker. (I've actually had that one.)

 

[Velocity173]

Descent will be made a sufficient distance from the clearance limit to allow for a normal descent, consistent with aircraft limitations and within the service volume and altitudes specified in the IAP.

That's a mouthful.

 

[Velocity173]

An audio panel failure would do it. So would simultaneous failure of both the headset and the loudspeaker. (I've actually had that one.)

Yeah too often we look at lost comms as only an radio issue. Worked an F-18 on departure once who lost comms immediately. Squawked 7600 as soon as he was airborne. Could've been a bad transmit switch or the mic in his mask went bad. Either way his NAV was good and continued to his destination.

 

[wabower]

Mine was total electrical failure while IFR but VMC between layers. Landed ASAP. ATC was thrilled.

I think the whole scenario is silly. A loss of all communications capability yet there's no loss of any other avionics?

 

[roncachamp]

Yeah too often we look at lost comms as only an radio issue. Worked an F-18 on departure once who lost comms immediately. Squawked 7600 as soon as he was airborne. Could've been a bad transmit switch or the mic in his mask went bad. Either way his NAV was good and continued to his destination.

That doesn't sound like a loss of all communications capability. He should still be able to receive and acknowledge reception with an ident.

 

[Velocity173]

That doesn't sound like a loss of all communications capability He should still be able to receive and acknowledge reception with an ident.

Sure if it's receiver only situation. I've had people plug in before and they could transmit and not hear. Had people where their entire helmet was inop as well. The point is a loss of commo isn't just the equipment installed in the aircraft.

 

[Lucky]

My plane has 2 VHF and a Sat Phone.

But the topic is 'Lost Comms' so that implies all comms, whatever that may be, don't work. Do most planes that can hit 390 have redundant systems? Sure. Its less likely maybe but the rules and procedures don't have exceptions carved out for that as far as I know.

So, put yourself in a CJ1 or P180 at 390 with a solid layer below you. TAF had your destination at mins and your alternate is 1,000' overcast. Comms are out...all. What do you do and why.

Hitting the IAF at 390 is VASTLY different than hitting it at MEA, and in real life you have to pick one course of action. What do you do?

Thee are always exceptions to rules and procedures. It's called an emergency which is at the pilot's discretion.

Personally, I've never looked at the specs of a CJ1 (which they don't make any longer) or a P180. However, let's look at a C510 with it's POS G-1000. If I've lost both comms, chances are I have a GFC failure which means I've lost a lot more than the comms and it is no longer a squawk 7600 issue but a 7700 issue.

BTW, to those that think that all the equipment that people have in high priced props and biz jets are things that feed people's egos, think again. All of the equipment that I have on my aircraft came that way from the factory. Why? For safety. Even a C510 comes standard with a sat phone. Another reason is regulatory. If you want your aircraft certified for RVSM operations (so that you legally can fly at FL290-FL410) you need to conform to a MEL that, among other things, includes (2) Mode S transponders. Redundancy make an emergency into an inconvenience. Big difference.

 

[denverpilot]

Yum...technology is good.

Same as I believed before reading the article

In the telco carrier business, "Backhoe Fade" of fiber circuits is a recurring joke because construction cuts a bejillion fiber lines and copper lines every day.

It was a regularly used phrase in outage conference calls. It also explained everything we needed to know to re-route stuff... if there even was an alternate route available or we could stuff new final destinations into SS7 databases to partially recover with some overload.

Those never ending public safety campaigns to "call before you dig" are ridiculously cheap compared to rolling a fiber splicing crew and truck.

Doesn't seem to help much, though... Or it's helping a lot and we'd all be amazed at how stupid people are. Not sure I like either real-world answer.

Seeing a system that's normally handling tens of thousands of calls go empty, and realizing the traffic has just "disappeared" somewhere upstream, is a really weird feeling sitting at the keyboard when you're the endpoint affected. And then the problem calls start... Fast busy/Reorder, switch tags/announcements of call not being able to be completed, dead air, etc...

People get cranky when the "magic" stops. Gotta keep those dial-tunez playin'...

 

[Lucky]

Seeing a system that's normally handling tens of thousands of calls go empty, and realizing the traffic has just "disappeared" somewhere upstream, is a really weird feeling sitting at the keyboard when you're the endpoint affected. And then the problem calls start... Fast busy/Reorder, switch tags/announcements of call not being able to be completed, dead air, etc...

That's because it isn't TSO'd.

 

[dtuuri]

All of the equipment that I have on my aircraft came that way from the factory. Why? For safety. Even a C510 comes standard with a sat phone.

When they first started putting phones in planes it was for the CEO not the Captain. Mr. Bigwig, though, couldn't understand how to make it work, so they also put a handset in the cockpit creating a significant non-operational distraction for the crew, finding a good channel, contacting mobile operators, reciting the permit number, and finally securing the party on the phone. Then, the crewmember had to let the CEO know it was time to pick up his handset. Then, you had to watch to make sure the call got disconnected when it was over, else tie up the channel preventing anyone else from using it and eventually receiving a whopping phone bill for dead air time.

Another reason is regulatory. If you want your aircraft certified for RVSM operations (so that you legally can fly at FL290-FL410) you need to conform to a MEL that, among other things, includes (2) Mode S transponders. Redundancy make an emergency into an inconvenience. Big difference.

I wouldn't call loss of a transponder an emergency, but I get your point. Transponders, though, have been installed in pairs for a long, long time--before RVSM, whether a legal requirement or not. If only one was onboard, you could continue the flight if it failed, but once you landed you were stuck. A second one was cheap insurance.

As for the HF, I know nothing about them other than one or two planes I've flown over the years had them installed. Nobody else knew anything about them either, so they just added weight. Wouldn't have been any help at all in a lost comm situation. YMMV.

I don't understand the need for three VHFs. Maybe the system design is such that the first two can both fail with the loss of a certain electrical bus. All I know is that every business plane I ever flew had only two and I never had a permanent loss of communications. None of my friends have that I'm aware of either. Had lots of temporary losses, though: Stuck mics, ATC transmitter or receiver problems, ATC failure to hand off before flying out of range, etc.

Dr. O has it right. All ATC needs to do is protect one altitude from/for you to your destination (essentially) and then the IAFs around it for complete safety. Palmpilot's dream rule would be far more difficult, impossible with multiple aircraft suffering the same problem due to an ATC outage.

Rant off. Let the fireworks begin.

dtuuri

 

[Lucky]

I wouldn't call loss of a transponder an emergency, but I get your point. Transponders, though, have been installed in pairs for a long, long time--before RVSM, whether a legal requirement or not. If only one was onboard, you could continue the flight if it failed, but once you landed you were stuck. A second one was cheap insurance.

My only point here is that it is required for RVSM.

As for the HF, I know nothing about them other than one or two planes I've flown over the years had them installed. Nobody else knew anything about them either, so they just added weight. Wouldn't have been any help at all in a lost comm situation. YMMV.

HF is used for SELCAL and is required for some international countries

I don't understand the need for three VHFs. Maybe the system design is such that the first two can both fail with the loss of a certain electrical bus. All I know is that every business plane I ever flew had only two and I never had a permanent loss of communications. None of my friends have that I'm aware of either. Had lots of temporary losses, though: Stuck mics, ATC transmitter or receiver problems, ATC failure to hand off before flying out of range, etc.

The 3rd VHF is used for the data link for things like PDC, D-ATIS, text and email messaging, etc.

 

[denverpilot]

HF is used for SELCAL and is required for some international countries

SELCAL is not required for HF. It does crap out during bad band conditions where there's too much noise to decode the tones.

It just makes it so you don't have to listen to static.

There's nothing requiring HF ops to have SELCAL.

 

[Lucky]

SELCAL is not required for HF. It does crap out during bad band conditions where there's too much noise to decode the tones.

It just makes it so you don't have to listen to static.

There's nothing requiring HF ops to have SELCAL.

I didn't say that. HF is used FOR SELCAL. I never said there was a requirement for ops to have HF for SELCAL. We happen to use it for our company fleet and it works fine. I used it once as a test

 

[taters]

Go to the airport decend to a fix shoot an approach make a phone call.
BUT don't discount your PIC emergency authority. usually its more than just a radio problem

 

[N801BH]

In the telco carrier business, "Backhoe Fade" of fiber circuits is a recurring joke because construction cuts a bejillion fiber lines and copper lines every day.

.

Absolute classic phrase...

I am gonna quote you on that for the rest of my life...

 

[Lucky]

Go to the airport decend to a fix shoot an approach make a phone call.
BUT don't discount your PIC emergency authority. usually its more than just a radio problem

Absolutely correct.

 

[denverpilot]

I didn't say that. HF is used FOR SELCAL. I never said there was a requirement for ops to have HF for SELCAL. We happen to use it for our company fleet and it works fine. I used it once as a test

Heh. That's like saying VHF is for TV. SELCAL isn't a verb.

It's just a series of tones. Can be used on anything that will carry audio, even a telephone.

 

[Lucky]

Heh. That's like saying VHF is for TV. SELCAL isn't a verb.

It's just a series of tones. Can be used on anything that will carry audio, even a telephone.

I don't think you get it.

 

[denverpilot]

I don't think you get it.

I get it. You're misusing the term. It's a technical standard not a verb or "something you do". A typical mistake of a user of a particular technology.

Saying you're "SELCALing" is like saying you're "iPhoning". We all get what you mean but it's a misuse of the term.

Even the Wikipedia page is borked. It claims a requirement of HF also.

SELCAL is just a standard for a dual tone alerting system. Quite similar to Touch-Tone(TM). They're both dual-time multi-frequency signaling standards.

Plug this software into a radio of any sort (well analog ones anyway...), doesn't matter if it's HF... You've got signaling with the SELCAL standard.

http://www.scannermaster.com/SELCAL_Decoder_Software_Download_p/31-521679.htm

One could do SELCAL signaling over anything. HF is just the common old use of it in aviation. There's better signaling standards out there, but aviation tends to stick to old stuff because the installed base of encoders and decoders isn't going to want to switch.

(Ironic considering the mandated updates to ADS-B bringing everyone into the early 1990's, technology-wise.)

I'm LTEing this to you. Ha. CDMAing even.