NorCal Approach [into SFO]

[SJ30]

Hello LiveATC.net!

Good to be with you here on this fine day.  I'm 41, getting back into aviation after many years of being out of touch with anything relative to flying.  I'll be isolating a full-time schedule [soon, I hope] for flight training from Private to some kind of Jet Type Rating, as there will be some high-performance aircraft in my near future.

Now, I've got some questions that I need help with:

Listening to NorCal Approach [inbound] into KSFO and using Google Earth to follow the in-bound aircraft as they make their way to the runway.  Several times now, I've heard pilots step on each other while trying to communicate with Approach Control.  I have not noticed any complaints from NorCal Approach yet, but as one who does not even have his private pilot license yet, it really is confusing to hear.

1) Why does this happen?

2) What happens if pilots flying their approach into the terminal control area don't get a response back from Approach Control soon enough, before getting too close to the transition point where Approach typically hands-off the aircraft to ATC?

3) I continually hear NorCal Approach Control asking these pilots to reduce their speed down to 180 kts.  I rarely hear a reduction lower than that, nor do I hear many reductions higher than that.  What is it about 180 kts that makes it so special for all of this IFR traffice in-bound to KSFO?  I'm looking at Google Earth and many of these aircraft are making initial contact with Approach Control at airspeeds in excess of 350 to 400 kts at anywhere from 12,000 ft to 8,000 ft as they descend from cruise altitude.

4) These guys talk really fast.  SLOW DOWN!  Just kidding, but some of these Controllers speak as though they work for an auto auction selling $1.7 million supercars!  They seem to be using a form of "short-hand" speak.  They don't use a lot of words.  For example, I might hear something like this:

Norcal, United465, descending 16 for 11, Tango.

In all honesty though, after sitting here and listening for a couple of hours straight, much of the structure of the language began to make some sense.  However, I still have a very hard time hearing the actual aircraft tail numbers being called by Control.  I have no idea how those pilots know for sure that Control is communicating with them.  It is almost as if these guys already know each other, and are merely going through the motions.  Otherwise, how they speak that fast and STILL know what the other is saying, really seems like a miracle.

Whatever these guys in ATC get paid, it ain't enough, IMO!

[nta522]

Have you done a bay tour in a Cessna before. It is very interesting because you will be on the same freq with all the big bird.

[tyketto]

Hello LiveATC.net!

Good to be with you here on this fine day.  I'm 41, getting back into aviation after many years of being out of touch with anything relative to flying.  I'll be isolating a full-time schedule [soon, I hope] for flight training from Private to some kind of Jet Type Rating, as there will be some high-performance aircraft in my near future.

Now, I've got some questions that I need help with:

Listening to NorCal Approach [inbound] into KSFO and using Google Earth to follow the in-bound aircraft as they make their way to the runway.  Several times now, I've heard pilots step on each other while trying to communicate with Approach Control.  I have not noticed any complaints from NorCal Approach yet, but as one who does not even have his private pilot license yet, it really is confusing to hear.

1) Why does this happen?

This happens when two pilots try to speak at the same time on frequency. Why does it happen? frequencies are often busy, and pilots are trying to check in so they are under control. Sometimes they end up being at the same time, and you hear the squelch from them stepping on eachother. When they do, neither the pilot nor controller can really hear what is being said, so someone may come up and say 'blocked'. Generally the controller will issue an instruction then, followed by a readback, then someone else will check in, and off they go again.

There was a documentary on Discovery or History channel that you may want to look at. Or better yet, search for the Tenerife incident on wikipedia. You'll find out that that accident was caused by pilots stepping on eachother on the tower frequency.

2) What happens if pilots flying their approach into the terminal control area don't get a response back from Approach Control soon enough, before getting too close to the transition point where Approach typically hands-off the aircraft to ATC?

Generally if the pilot is worried about that, they'll remind the Approach controller:

"You want Redwood 1948 over to tower?"
"Redwood 1948, sorry about that, contact Tower 120.5."

Something to that effect.

3) I continually hear NorCal Approach Control asking these pilots to reduce their speed down to 180 kts.  I rarely hear a reduction lower than that, nor do I hear many reductions higher than that.  What is it about 180 kts that makes it so special for all of this IFR traffice in-bound to KSFO?  I'm looking at Google Earth and many of these aircraft are making initial contact with Approach Control at airspeeds in excess of 350 to 400 kts at anywhere from 12,000 ft to 8,000 ft as they descend from cruise altitude.

It isn't just KSFO. It happens just about everywhere. What it does is it keeps aircraft separated at the same exact distance in the arrival stream. If the first plane is doing 180kts, and your second plane is 3 miles behind at 180kts, there should be 3 miles separation all the way until the first plane slows down. More often than not, you'll hear something like "maintain 180kts until the outer marker" or something to that effect (listening to the KLAS feed, the Final controller there generally gives "maintain 180kts until 7 mile final, contact Las Vegas Tower 119.9").

As far as Google Earth goes, if they are making contact with Approach at that speed, there's a problem, unless GE is showing ground speed. There's a standing order that unless directed by ATC, you can't exceed 250kts under 10,000ft MSL. Having a look at BSR2 arrival, there is a crossing restriction at the BOLDR intersection of 250kts Indicated airspeed (not ground speed). My guess is Google Earth is showing you ground speed.

4) These guys talk really fast.  SLOW DOWN!  Just kidding, but some of these Controllers speak as though they work for an auto auction selling $1.7 million supercars!  They seem to be using a form of "short-hand" speak.  They don't use a lot of words.  For example, I might hear something like this:

Norcal, United465, descending 16 for 11, Tango.

In all honesty though, after sitting here and listening for a couple of hours straight, much of the structure of the language began to make some sense.  However, I still have a very hard time hearing the actual aircraft tail numbers being called by Control.  I have no idea how those pilots know for sure that Control is communicating with them.  It is almost as if these guys already know each other, and are merely going through the motions.  Otherwise, how they speak that fast and STILL know what the other is saying, really seems like a miracle.

What you're seeing is that pilots aren't bound by actual phraseology like ATC is. Pilots could pretty much readback whatever they want as long as it is understood by the controller, whereas the controller has phraseology he must follow. For example, if a controller needs to give advisory to a large aircraft behind a heavy, he/she may say something like:

"Cactus 594, traffic 12 o'clock, 5 miles, 8000ft and descending, heavy Boeing 767."

The AWE jet looks for him and sees him: "Traffic in sight, Cactus 594."

Controller gives the wake turbulence advisory: "Cactus 594, follow that traffic, caution wake turbulence, cleared visual approach runway 25L."

Pilot reads back "Follow the big bird, watch for the bumps, cleared visual 25L, Cactus 594."

Whatever these guys in ATC get paid, it ain't enough, IMO!

Agreed!

BL.

[athaker]

4) These guys talk really fast.  SLOW DOWN!  Just kidding, but some of these Controllers speak as though they work for an auto auction selling $1.7 million supercars!  They seem to be using a form of "short-hand" speak.  They don't use a lot of words.  For example, I might hear something like this:

Norcal, United465, descending 16 for 11, Tango.

In all honesty though, after sitting here and listening for a couple of hours straight, much of the structure of the language began to make some sense.  However, I still have a very hard time hearing the actual aircraft tail numbers being called by Control.  I have no idea how those pilots know for sure that Control is communicating with them.  It is almost as if these guys already know each other, and are merely going through the motions.  Otherwise, how they speak that fast and STILL know what the other is saying, really seems like a miracle.

When I first started listening to ATC I had no idea about half of the stuff being said.  But that's one of the great things about this site, especially for future pilots (like myself, not soon enough) - Listen as much as you can. and you'll pick up the phraseology, procedures, and even decipher what they're saying. Don't understand the lingo? Google search or just ask these forums...most helpful controllers and pilots in the world here!

I can now even understand ridiculously fast helicopter clearance clips from that great former tower controller at KJFK!

[SJ30]

Have you done a bay tour in a Cessna before. It is very interesting because you will be on the same freq with all the big bird.

When I was in my teens, I initiated primary flight training and got through about 3.5 hours before I got side-tracked by other things [mainly school and family issues].  My very first lesson was out of Oakland's North Field, Alameda Aero Club.  We flew the Tiger Grumman and I loved that little airplane.  Back then, main movie for wannabe pilots was Top Gun and I recall hearing the theme music in my head while doing the pre-flight of the aircraft.  Our practice area was northern San Pablo, just outside the terminal control area.  So, I do remember my CFI engaged with Oakland Tower and I think on one or two occasions, even Bay Departure [if I can recall correctly].  Back then, I knew I had a lot to learn as you not only have to fly the airplane, but you also have to stay engaged on the radio as well.

Later, during my second return to aviation after school was over, I worked with Oracle in Redwood Shores and finally made it back to flight training.  This time, I flew out of PAO and SQL.  I had a grand total of two training flights out of SQL and one training flight out of PAO [when my instructor could not make it to SQL] and that was it.   Once again, I got side tracked by life and ended up not being able to finish.  By now, I had a grand total of no more than 5 hours dual given.  But, I remember my CFI on the radio having to remain clear of any SFO traffic.  The practice area was typically near the ridge up along the 280 corridor south of Stanford University [I remember seeing the red roof tops on the way back to the airport].

When I first started listening to ATC I had no idea about half of the stuff being said....

Hey, thanks!  I'm sure I'll have many more questions for the pros here.

I purchased the So-To-Speak Radio Communications audio tape program a long time ago, but never really began studying it until recently.  I plan to go through the audio program several times.  It has helped a great deal.

My problem is not with the structure of the language.  My problem is the speed with which these guys communicate with each other.  The So-To-Speak audio program really helps me to understand what must get said, but it does not help you with the light-speed delivery that you get when listening to live radio.  Also, the So-To-Speak program teaches you to use whole phrases, not the shorthand phraseology.  So, my brain knows what should be said, but I keep waiting to hear the pilots and controllers use the same "longhand" phraseology.

I think these guys are so used to communicating on the radio, that for them, they have no problem in shorthand communications and nothing gets lost in the translation with them.  I think sooner or later, I will be able to keep up with the shorthand pace AND the rate of speed at which it gets delivered from controller to cockpit and cockpit to controller.

One of the things I wish they would do however, it more clearly articulate and enunciate their Constants and natural Vowels.  That way, even with the speed at which they speak, my brain could still catch-up to what they are actually saying.  Often times, they blur their Constants and Vowels together and when you couple that with the rate of speed at which they communicate, it really makes it difficult to understand.

For example:

Control might say - "Norcal, United564....."

But, it sounds like - Nickel, UnitusFa64..."

I actually heard one pilot come in to the airspace and deliberately reduced his rate of speech by at least 300%.  Control was speaking at light speed, but this pilot slowed things down for them quite a bit and he maintained that slower rate of speech all the way to "frequency change approved, contact tower..."  He was also flying a heavy, so not an inexperienced pilot in the least.

There was a documentary on Discovery or History channel that you may want to look at. Or better yet, search for the Tenerife incident on wikipedia. You'll find out that that accident was caused by pilots stepping on eachother on the tower frequency.

Thanks for the detailed reply!

I understood the technical reason behind the squelch.  What I was hoping to understand with my question was, why these professionals were stepping on each other.   I would expect, from time-to-time to hear low-time, low-performance aircraft pilots occasionally engage in stepping on each other, but I was not expecting to hear so much of it from the professional ranks.   I was just curious as to why commercial pilots were continuously doing this and whether or not there was a potential solution forthcoming that would prevent such errors?

I'll go check out that Tenerife accident documentary.  Thanks for the tip!

Generally if the pilot is worried about that, they'll remind the Approach controller:

"You want Redwood 1948 over to tower?"
"Redwood 1948, sorry about that, contact Tower 120.5."

Something to that effect.

Yes, I do recall hearing more than one "sorry" out there from both pilots and controllers, but they always seemed to rectify the problem without allowing things to escalate into a real problem - at least last night they did.

It isn't just KSFO. It happens just about everywhere. What it does is it keeps aircraft separated at the same exact distance in the arrival stream.

Thanks - I understood the need for Control to keep traffic at a relatively uniform distance in order to better facilitate efficient flows into and out of the system.  But, why 180 kts?  Is there something special about 180?  Why not 160, 190, or 200, or some other number that is well above the stall speed of these aircraft?  Or, does this have something to do with the fact that most of these aircraft are high-performance jets?

As far as Google Earth goes, if they are making contact with Approach at that speed, there's a problem, unless GE is showing ground speed.

They are actually showing "kts" and "msl."

I just realized that Google Earth is running under a 5 minute delay.  At 400 kts, that equates to about 33.3 nautical miles.  At 250 kts, that equates to about 20.8 nautical miles.  So, when I overlay that distance onto my observations, the problem does go away.  They would have 33 to 20 miles to reduce speed down to under the 250 kts limit, which from 400 kts should not be that difficult to do - I would guess.   Correct me if I am wrong.

What you're seeing is that pilots aren't bound by actual phraseology like ATC is. Pilots could pretty much readback whatever they want as long as it is understood by the controller, whereas the controller has phraseology he must follow.

I did not know that.  When I go through the So-To-Speak audio tape series, the continually stress that the pilot should always read-back almost verbatim what control communicated.  That way, there is no confusion.  That's why I said that it seemed very hard to accomplish that task, when the controller is on the ground and can focus more on a screen directly in front of them, whereas the pilot has to divide their attention to flying the aircraft, listening to control and monitoring the instruments - all at the same time.  So, the amount of brain capacity available for listening and reading-back radio calls, is not the same for the pilot as it is the controller.

For the first time, I'm hearing you say that the PIC does not have to give a verbatim read-back.  And, come to think of it, many of the pilots that I listened to yesterday, did not give verbatim read-backs.

On the other hand, I have the Jeppesen, King Schools and Sporty's Private and Instrument DVDs and in particular, they stress early on that during certain ground and flight operations, the pilot in command must offer verbatim read-backs of certain kinds of ATC communications.

For example: 

Taxi into Position & Hold instructions.
Taxi and Remain this Frequency instructions.
Taxi and Contact This Frequencdy when Ready instructions.
and others...

Can you explain the differential/justification between/for giving verbatim read-backs and mere read-backs?

Again, thanks for your detailed reply!   

[tyketto]

Hey, thanks!  I'm sure I'll have many more questions for the pros here.

I understood the technical reason behind the squelch.  What I was hoping to understand with my question was, why these professionals were stepping on each other.   I would expect, from time-to-time to hear low-time, low-performance aircraft pilots occasionally engage in stepping on each other, but I was not expecting to hear so much of it from the professional ranks.   I was just curious as to why commercial pilots were continuously doing this and whether or not there was a potential solution forthcoming that would prevent such errors?

They mentioned something about new technology that would help resolve stepping on eachother in the Tenerife documentary, but what it was escapes me at the moment. Most pilots whether commercial, general, private, or otherwise just try to get in as quick as they can so they don't cause trouble for the controller. Most should wait until there is an open moment (and that would be the best), but they don't, and it just happens.

I'll go check out that Tenerife accident documentary.  Thanks for the tip!

It isn't just KSFO. It happens just about everywhere. What it does is it keeps aircraft separated at the same exact distance in the arrival stream.

Thanks - I understood the need for Control to keep traffic at a relatively uniform distance in order to better facilitate efficient flows into and out of the system.  But, why 180 kts?  Is there something special about 180?  Why not 160, 190, or 200, or some other number that is well above the stall speed of these aircraft?  Or, does this have something to do with the fact that most of these aircraft are high-performance jets?

To be honest, its up to the controller. I hear 180, 170, 160, or even 150, depending on the airport in question, traffic, runway configuration, the whole lot. So a lot comes into play for speed restrictions, but mainly it is up to the controller on how they want their traffic sequenced; both laterally and vertically.

As far as Google Earth goes, if they are making contact with Approach at that speed, there's a problem, unless GE is showing ground speed.

They are actually showing "kts" and "msl."

I just realized that Google Earth is running under a 5 minute delay.  At 400 kts, that equates to about 33.3 nautical miles.  At 250 kts, that equates to about 20.8 nautical miles.  So, when I overlay that distance onto my observations, the problem does go away.  They would have 33 to 20 miles to reduce speed down to under the 250 kts limit, which from 400 kts should not be that difficult to do - I would guess.   Correct me if I am wrong.

I think what is happening, is that they are showing true airspeed (TAS) versus hearing Indicated airspeed(IAS) on the feed. These should show you the difference between the two (warning, very detailed and mathmatical)

http://en.wikipedia.org/wiki/Indicated_airspeed
http://en.wikipedia.org/wiki/True_airspeed
http://en.wikipedia.org/wiki/Ground_speed

That should give you more insight into what Google Earth is showing for speed.

What you're seeing is that pilots aren't bound by actual phraseology like ATC is. Pilots could pretty much readback whatever they want as long as it is understood by the controller, whereas the controller has phraseology he must follow.

I did not know that.  When I go through the So-To-Speak audio tape series, the continually stress that the pilot should always read-back almost verbatim what control communicated.  That way, there is no confusion.  That's why I said that it seemed very hard to accomplish that task, when the controller is on the ground and can focus more on a screen directly in front of them, whereas the pilot has to divide their attention to flying the aircraft, listening to control and monitoring the instruments - all at the same time.  So, the amount of brain capacity available for listening and reading-back radio calls, is not the same for the pilot as it is the controller.

For the first time, I'm hearing you say that the PIC does not have to give a verbatim read-back.  And, come to think of it, many of the pilots that I listened to yesterday, did not give verbatim read-backs.

On the other hand, I have the Jeppesen, King Schools and Sporty's Private and Instrument DVDs and in particular, they stress early on that during certain ground and flight operations, the pilot in command must offer verbatim read-backs of certain kinds of ATC communications.

For example: 

Taxi into Position & Hold instructions.
Taxi and Remain this Frequency instructions.
Taxi and Contact This Frequencdy when Ready instructions.
and others...

Can you explain the differential/justification between/for giving verbatim read-backs and mere read-backs?

Again, thanks for your detailed reply!   

Sure. Pilots are required to read back the following: runway assignments, hold short instructions, TIPH instructions. This is primarily to prevent runway incursions and operational errors by the Local controller, but also keeps the pilots safe from any incidents of their own. Case in point: An arrival lands on 28R at KSFO.

ATC: Cactus 654, hold short of runway 28L, remain on this frequency.
Pilot: we'll hold short of the left, Cactus 654.

Which 'left' is the pilot referring to? He's on 28R/10L so it couldn't be that one, but is he holding short of 28L, 1L, or 19L? ATC can't assume that he knows, and there have been times when a hold short instruction has been given, and the aircraft that should have held short entered the other active runway.. while a departure was on their takeoff roll.

So they (pilots) must read back the runway assignment and the hold short instruction. ATC will remind the pilot that they need to hear the runway with the instruction:

ATC: Cactus 654, read back hold short of runway 28L.
Pilot: We'll hold short of 28L, Cactus 654.

So at the places where readbacks are required for pilots, those readbacks will be used; at other times, 'shorthand' will be used.

BL.

[SJ30]

Thanks, BL!  That pretty much clears it up for me - I appreciate the details.   

[djmodifyd]

i don't think i could possibly add anything else to this..those were some great replys!

i'll just add that 170 is my "magic" speed on final...usually 210 on downind, 170 base, and 170 to the marker...
that can also change...but that is usually the speed i use

i use that because i've heard that 170 is a dirty speed and 210 is a clean speed....anything in between is a "mix" of dirty and clean and its a harder configuration for pilots.

[sykocus]

They mentioned something about new technology that would help resolve stepping on eachother in the Tenerife documentary, but what it was escapes me at the moment. Most pilots whether commercial, general, private, or otherwise just try to get in as quick as they can so they don't cause trouble for the controller. Most should wait until there is an open moment (and that would be the best), but they don't, and it just happens.

CPDLC perhaps. It's often touted as the answer to frequency congestion. It has it's place but I can't imagine it taking over for radios in the terminal environment.

[KSYR-pjr]

Taxi into Position & Hold instructions.
Taxi and Remain this Frequency instructions.
Taxi and Contact This Frequencdy when Ready instructions.
and others...

Can you explain the differential/justification between/for giving verbatim read-backs and mere read-backs?

Are you sure that those ground school training DVDs listed all of those above as being required?  The first example in your list and "Taxi to... hold short rwy XX" or "... hold short taxiway XX" instructions are required to be read back as part of a several year old FAA directive to lower runway incursions, but the second and third on your list are not required to be read back verbatim.  In fact, at busy airports the ground or tower controllers would probably prefer a less-is-more type of readback for those.

In the case of the second on your list, I always make it a point to simply reply, "Bonanza XXX, Wilco, good afternoon" if the tower's instruction is simply that.  And the "good afternoon" is not necessary but since I won't be talking to the controller again I like to at least be courteous.   ATC communication purists would complain, though.  On the other hand, if the tower includes any "hold short" instruction to that one (either hold short another runway or a taxiway), I do read back it all verbatim.

[SJ30]

CPDLC perhaps. It's often touted as the answer to frequency congestion. It has it's place but I can't imagine it taking over for radios in the terminal environment.

This link seems to give a good overview of CPDLC.  I used to work in the enterprise software industry, so I'm familiar with Data Link technology.  This one tends to rely upon the transmission of text messages or possibly FRL [flat record layout] formats.  The FRLs [if used] would require some parsing on the receiving end [inside the aircraft] and so would the text.  The part that really interests me about CPDLC coming from the technology business myself, is the ability for Control to push out a message that gets received by the on-board FMS.  But, the same would be true of the pilots ability to down-link messages through the FMS to Control.

This sounds like it would be good for en route flying, not sure I see the benefit(s) for flying approaches in congested airspace unless all the flight segments from initial descent down through entering under the authority of Approach Control and then being handed-off to Tower, were be supported by a normal exchange of up-links and down-links between Control and the FMS automatically - leaving the pilot with little to do in this regard other than simply reading the message/instructions directly on his/her PFD or MFD.

My biggest concern would be whether or not the FMS was getting the right message, intended for the right aircraft a the right time in the sequence of events!  Having worked with enterprise technology in the past, I would need a whole lot more than a proof-of-concept before I would feel comfortable with such a system.  But, that is just the old systems engineer coming out in me, I guess.
 

http://members.optusnet.com.au/~cjr/CPDLC.htm

KSYR-pjr,

Hey, thanks for the reply.

Yes, that's what I'm seeing in my videos and it is also what I am hearing in the So-To-Speak audio tape series on Pilot to Control communications protocols.  I'm actually doing this while driving as it is the best simulation for flying that I can come close to in my car.  I have to drive and listen to and reply to instructions from ATC on the tape.  Sometimes people catch me talking with no one else in the car with me. 

I've gotten some strange looks before, but they don't know that I'm reading back instructions or calling control with a request via what I'm hearing on the tapes.   Of course, some of the other drivers on the road or street just think I'm crazy, lol! 

I figure that if I can make radio calls while paying firm attention to the increasingly lunatic traffic on the road, then I can make radio calls in the smoother more calm traffic in the air.  We shall see if all this audio tape training helps once I begin my actual dual training.  But, yes - they are stressing that some of control's instructions get read back verbatim.  I think I listed those that they set fourth as such, correctly.  I'll double check.

[KSYR-pjr]

I've gotten some strange looks before, but they don't know that I'm reading back instructions or calling control with a request via what I'm hearing on the tapes.   Of course, some of the other drivers on the road or street just think I'm crazy, lol! 

Throw one of those cellphone earpieces in and you will fit right in with the rest of the traffic.    Great use of the commute dead time, by the way.

[KSYR-pjr]

Yes, that's what I'm seeing in my videos and it is also what I am hearing in the So-To-Speak audio tape series on Pilot to Control communications protocols. 

Oh, and regarding the required calls:  I have heard tower and ground controllers give pilots a very hard time for not reading back hold-short instructions by continually asking for the readback until it happens, which demonstrates the importance of a hold short readback.   

I have never heard ATC give pilots a hard time for failing to read back the "taxi to the gate/ramp and remain on this frequency" instruction.  In all cases abbreviated pilot readbacks were met with a "See ya/good day" or some such pleasant controller response, or nothing at all.

[SJ30]

I have never heard ATC give pilots a hard time for failing to read back the "taxi to the gate/ramp and remain on this frequency" instruction.  In all cases abbreviated pilot readbacks were met with a "See ya/good day" or some such pleasant controller response, or nothing at all.

I'll certainly keep that in mind, check the regs (FARs) and ask my instructor once I pick one and start dual training.

I'm trying to learn as much as I can before I begin my dual.  So, I'll be going over the Jeppesen, King and Sporty's programs several times before I begin, so that I can hit the ground with a good framework of knowledge and so that I can hit the ground asking good questions of my instructor from day one.  I'm also trying to reduce the training time and make it as focused as possible on those thing that will make me a better and more proficient pilot down the road when I start flying my high performance light business jet and other high-performance aircraft that I have in mind as "fun" planes.