Pis*ed off by a speed restriction? Read this.

[2R]

It should be like water off a ducks back.Changing speeds is just something else to do and i would rather slow down at altitude and save fuel than be given a hold low level and burn money .
Nice to know that other pros share our concerns.

Their are a lot of considerate people in this industry practising random acts of kindness.

A friend of mine done me a kindness one day when i wanted to help him back ,he said " oh no pass it on to someone else it will get back around the world for me eventually"

[justplanecrazy]

Good post. (a certain bag run flying metros came to mind when I read it ) I always find it humerous when someone is following another aircraft and told to reduce to minimums at 10 miles, but despite being low already and having an aircraft that can reduce speed in a matter of seconds, they completely ignore the instruction. I've only had consistent problems with one company and they've ended up going around or spinning on a regular basis. As a result, they end up in the air longer than any other company that listens to my instruction. The other bag runs flying the same planes always sucks the speed back right away, giving me just enough room to get the cessna down and off the runway before landing them behind. I don't know, maybe they figure that the phraseology #2 follow the cessna, shouldn't exist. I always get a kick out of it though because they don't seem to get it. It's like they figure if they take a run at the field, I'll scatter everything smaller to make them number 1.

Metro comes over to tower 5min's back of the field...
#2 follow the cessna on left downwind, start coming back on the speed.
##### come right back to minimums, your traffic about to turn base.
##### (now grounding 250kts vs. 200kts a few minutes ago) confirm you're right back to minimums?
a few seconds later... ##### pull up and go around.
...15 min's later the same plane touches down.

This went on regularly for the past 12 months and it's only the past few months that they've started to actually obey the instructions. I think they're finally starting to catch on. I was always tempted to call them up to the tower and show them an overtake scenario and what we're dealing with. To write it on paper so others actually understand it, is kinda hard.

[hind sight]

Did you ding them with a violation for busting the regs?

[flyinhigh]

Originally posted in the "ATS Question Forum" but it is an important consideration for pilots flying all types, so I am posting a link here. If the mods don't like that, feel free to remove this post.

I think a better understanding of this concept can serve to reduce pilot frustration in busier airspace.

http://www.avcanada.ca/forums2/viewtopic.php?t=29346

Excellent post, I have asked questions in the ATC foroum but quite awhile ago on how all this works. There is one leg in particular that we get slowed waaaay down routinely which after awhile does get frustrating, just like you said a king air is a fair amount slower than what I am in.

Nice to have it broken down so nicely. Keep up the good work

[W0X0F]

CPL_ATC,

Good subject and good start for a topic. Of course ATC has a job to do slotting in arrivals. Speed limits help to facilitate this a degree. As you pointed out, it is hard for faster planes to overtake slower ones for the reasons stated AND generally they would also have to be descended through the altitude of the leading airplane.

I have no beef with being slowed to fit into the arrival parade because as you also pointed out, I'll be blocking others as often as I am blocked.

What does make a difference to me is the way some controlers create the line-up.

Being slowed is fine. The sooner the better since it only requires a small correction early on to build in the space.

I try to maintain a situational awareness about where I am in the arrival flow and adjust flight to fit in.

What I dislike is being widened out. It is the worst because I am penalised threefold; Time, Fuel, (low alt burn) Distance.

It has been my experience that the more experienced controlers make more use of speed changes and those with lesser experience use vectors.

I raise this point for awareness.

Controlers, please slow us but keep us pointed at the airport as best you can.

Pilots, when you receive that first vector that widens you 10° outside of the beacon, it's a clue that you need to build in some space. Offer to slow up some or you'll be vectored another 10°+ wide and then have to come back low and slow.

[arctic navigator]

Great post. Would be nice to see Calgary Terminal and Edmonton Center use this approach a little more. More often than I can count I've been vectored off to la la land at normal cruise to give spacing between aircraft ahead when i would have been more than happy to pull the speed back by 50kts and save the fuel while arriving at the same time anyways.

[Jerricho]

It has been my experience that the more experienced controlers make more use of speed changes and those with lesser experience use vectors

Speed control is certainly a finesse skill that comes "with age" . I've joked with trainees before about "get them all doing the same speed, and sequencing is a piece of piss". As some of you drivers there have already noted, burning fuel while keeping the speed on and then being widened out does cost dollars. One situation though we see often is when the arrival has hung it up right to the last possible mile and points the nose down. We're all very aware of screwing with a speed and what it can do to a descent rate.

On the other side of the coin, I'm sure many pilots out there aren't too fond of the accordion "slow down......speed up......slow down......speed up....sh*t right back to final approach speed" (me personally, I don't like issuing a "reduce to final", but that's just how I was taught).

IMHO, this once again brings out the old chant........... yet ANOTHER reason for familiarisation visits so both sides can view first hand the interaction of what we all do.

[W0X0F]

So we are in agreement,

So if it comes down to putting someone on a vector vs. speed control, speed control will generally be the preferred tool for the controller.

I frequently find myself on a right hand approach with another on a long straight in. I'll gladly slow early on and stay pointed at the beacon yet some controlers wish to send me left to fall in behind the straight in traffic.

I think to myself that there is room for 4 dimentional thinking.

[trey kule]

I really enjoyed this post. Never really thought much about the math limitations before.

More posts about ATC inside stuff like this would be nice if you folks have the time.

[FamilyGuy]

A Terminal controller would a got em in #1

[Flying Nutcracker]

Great topic and very insightful!

Just to play the angry devil... do the math by slowing the King Air 30kts... at 100NM.

[Flying Nutcracker]

And just for fun slow the King Air 30kts at 80NM. It will give a 10NM spacing with the Metro ahead at 15NM from the Airport... The extra flight time for the King Air would be 2 minutes...

It's funny how it works both ways... either way ATC has the ultimate picture of the traffic, and this math is pretty interesting! It has given me great insight as to how it is applied. 2 airplanes going the same way is one thing, but when you have 10, 15, 20 airplanes coming in from every direction it gets even more interesting...

Oh... and by the way... I do have a lot of time on my hands!

[bigfssguy]

Jerricho brought up a valid point that should be stressed. There are not enough Familiarization trips. Not enough pilots take the time to go up to a tower or pop into a center or FIC to see what the other side is doing unless there going up to have coffee witha buddy. I know most ATC and FSS jump at the chance to check out what pilots do.

I invite all pilots to come for a visit when they have an opportunity. All it takes is a quick phone call to your local Tower, ACC, FSS or FIC to schedule a time and usually you'll get the whole tour. Not only will you see what we do, you also get to see how the other half lives. Nearly everytime someone ha s come up to my tower for the first time i get the ol' "Wow i didn;t know you were doing all that" line. I really think it is a valuable tool for both sides of the mic.

[Pygmie]

Everyone would benefit from something like that.

Yes, but us controllers with our security clearances pose too high a risk by being up front.

[whipline]

Here is a scenerio for you CPL. Recently we were going into and East coast airport with a FSS. We (737) were heading straight to the IF of the active runway. Another aircraft (challenger) was heading to a non active runway to do a practice approach. The other aircraft was going to be at their IF first (non active) but would have been second to the active IF.

Would you vector the aircraft doing the practice approach or would you give us a hold clearence?

[gonefishin']

would love to come and visit YVR ACC and see the show, but now that it has moved to Surrey, I am frightened to come and visit...

[tesox]

Im interested to hear pilots opinions of flying into ydf yyt and yqx...not a lot of speed adjustments applied here although I think we have a very unique traffic construct.

[tesox]

Whipline, what constituted the "active" runway at the FSS served airport? In my opinion a training flight conducting practice approaches when IFR traffic are due will get speed adjustments from me to arrive after...I have a hard time issuing a hold to an IFR sched flight while a training flight is conducting their work...I also like to think the pilot doing the training might appreciate not having that added pressure of getting clear of the area in a mad rush to help...

[lilfssister]

Here is a scenerio for you CPL. Recently we were going into and East coast airport with a FSS. We (737) were heading straight to the IF of the active runway. Another aircraft (challenger) was heading to a non active runway to do a practice approach. The other aircraft was going to be at their IF first (non active) but would have been second to the active IF.

Would you vector the aircraft doing the practice approach or would you give us a hold clearence?

Was the other aircraft IFR doing practice approaches or VFR doing practice approaches? If they were VFR doing approaches the ACC might not have had any idea they were there.

Were you told it was the "active" runway by FSS or ATC?

According to our MANOPS someone doing only a low approach and overshoot does not make a runway active, they are supposed to just be given as traffic.

Because a runway is "active" in the FSS environment does not mean EVERYONE has to use it. You can use any runway you want. Providing you don't conflict with traffic using other runways you can elect to use any runway. I've had three active runways, and had a pilot elect to use the fourth (i.e. oppposing end of one of the actives) and have that be the best idea for all concerned.

[swordfish]

That original post, and the explanatory link, were indeed very good.

What I don't understand is why the overtaking a/c cannot overtake the slower one beneath him. i.e. if you're going 20 kt faster than the first one and ATC knows you're going to be there first at normal flying, why can't you assign the faster a/c a lower altitude to start with?

We frequently have this conflict from YQU to YYC where a BA32 takes off shortly after a BA31. There is a 15 kt TAS advantage for the -32 in cruise but a 30 kt advantage for the -32 on descent (higher Vmo). Over the next 316 nm, there is lots of opportunity to get the 32 ahead of the 31, and on descent, the 32 is going to pull well ahead of the 31. Using vectors AND speed it would appear simple to to get the 32 ahead by the time you get to Calgary.

If we both get the same altitude, I can see that we have to maintain horizontal separation. But if we are separated vertically, what is the issue with one overtaking the other, beneath him?

It would appear to be more practical to me to slow the 31 IF NECESSARY rather than slow the 32 right up first in cruise, then intolerably frustratingly on descent.

The other issue is 10-12 miles separation; that's 3 minutes if one of them is standing still i.e. a long separation distance. Is that really necessary? What kinds of things can go wrong that would cause a conflict for 2 planes going in the same direction? Why can't it be 5 miles?

No matter how you enter the terminal, the Terminal Controller just gives you vectors. Unless we are the lead a/c to start with of course. The sweetest thing a TC gives us is: "Keep your speed up; you're number 1"

Perhaps cpl_atc can throw some light onto this.

[whipline]

Thanks for the Reply's!! Both aircraft were IFR. The runway was active because the wind was 20 knots down the pipe, the other aircraft was heading to the other end of it.

I was also wondering why the controller didn't vector the aircraft doing a practice approach behind us. Next time I'll just cancel and land and let them sort it out on their own.

[tesox]

Whipline, out east we dont provide vectors into FSS served airports because those airports do not have established vectoring maps or altitudes...FSS airports here do not have the required ground based radars to provide this service and that is why you may be experiencing a transfer or seam in ATC services, plus we dont have immediate communications with the FSS to establish radar separation standards. We here use procedural separation standards to get aircraft flying until they are on radar where we adjust the separation used and of course vice versa...aircraft going into the FSS served airport are separated prior to going off our radar. In your particuliar case the training flight may have indicated to ATC it was going to cancel IFR at a certain point on the approach thus giving the second sched IFR no need to be delayed...by the ACC. Im only trying to present reasons why this may have happened to you.

Regarding the faster overtaking slower...too many variables to give a concrete answer, if both are enroute to a runway they are lined up for, it can be really challenging to get the faster one in first in some situations, if both aircraft are going for a runway offset from their inbound track by 45 or more, than it is a joy....I ask the pilot what they prefer based on the situation...whether to be vectored or laddered down or get lower before a certain distance behind the first....I dont fly the machine, so I like to give the options so that everyone gets what they want...especially me!! HA.

I also wanted to add that I never put two at the same altitude unless they are similiar type separated by 10 miles or more or the faster is ahead...too easy to get distracted by something....

Like I said before, YQX low level is a unique challenge....now im rambling....sorry

[justplanecrazy]

What I don't understand is why the overtaking a/c cannot overtake the slower one beneath him. i.e. if you're going 20 kt faster than the first one and ATC knows you're going to be there first at normal flying, why can't you assign the faster a/c a lower altitude to start with?

We frequently have this conflict from YQU to YYC where a BA32 takes off shortly after a BA31. There is a 15 kt TAS advantage for the -32 in cruise but a 30 kt advantage for the -32 on descent (higher Vmo). Over the next 316 nm, there is lots of opportunity to get the 32 ahead of the 31, and on descent, the 32 is going to pull well ahead of the 31. Using vectors AND speed it would appear simple to to get the 32 ahead by the time you get to Calgary.

I don't work IFR but I spend a lot of time watching speeds and understand enroute's and terminal's dillemmas, as I watch them everyday and like to play with the numbers. I can't recall the JS31/32's regular ground speed at cruise so I'm going to pick some numbers that are probably fairly close and try and work out the scenario. IFR guys please correct me if I'm way off base.

If your JS31 departs 5 minutes ahead of you, and averages 180kt's TAS on the climb out, by the time you depart he's now 15nm ahead. He's also hit his cruise altitude 5 minutes sooner and is still making significant ground on you. So by the time you both level off in cruise, you probably have at least 20nm seperating you. If the leader is grounding 235 and the 2nd grounding 250 and you have 275nm to the destination, it would take you a little over an hour to overfly your destination. If you were overflying, at the point you crossed the destination, the 2nd guy would still be around 3nm behind the first guy. In order to get the 2nd guy 10nm in front, you'd have to start the 30kt advantage (descent) 30 minutes back or 120nm from the field. On top of this I believe enroute would have to have you spaced around that distance when handing you off to CYYC terminal as well. That means that you'd have to subtract another 50nm from the 275nm of airspace where they can pass you. Instead of starting the descent at 120nm you'd now be leaving cruise 170nm from the field. Now factor in the slower airspeed once you've reached your mea while the JS31 is still at cruise with a higher TAS and it probably isn't even physically possible. They'd have no choice but to slow the guy in front and drive you at the field.

It would appear to be more practical to me to slow the 31 IF NECESSARY rather than slow the 32 right up first in cruise, then intolerably frustratingly on descent.

The amount they'd have to slow the guy in front would probably be significantly more than they'd have to slow you. Basically what you're saying is why do I have to do I have to shovel the driveway instead of him. One of you has to get penalized and the penalty would be the same for both. So instead of trying to get fancy by hanging the first guy up nice and slow and driving the second guy low and fast, they simply try and keep the first guy as fast as possible and start the second guy back on the speed. What would really be of best interest to you and the controller, is to talk to dispatch and figure out how you can juggle your schedules so that you are departing 5 minutes ahead of the JS31.

The other issue is 10-12 miles separation; that's 3 minutes if one of them is standing still i.e. a long separation distance. Is that really necessary? What kinds of things can go wrong that would cause a conflict for 2 planes going in the same direction? Why can't it be 5 miles?

Calgary is always running multi runway operations. They're continuously threading the needle and depending on towers departures, they have to have anywhere from 2 to 5 miles at the intersection if I remember right. In order to get 5 miles at the intersection, they need the planes for each runway perfectly spaced 10 miles apart. The other thing you don't see as a pilot is how quickly that seperation reduces as everyone comes to a stop. Look at a group of cars coming to a red light. You were all spaced perfectly a few minutes ago but as the first cars approach the red light and prepare to stop, the rest of the traffic quickly bunches up behind them. It's a ripple effect and the exact same thing happens as aircraft slow down to land at a field.

No matter how you enter the terminal, the Terminal Controller just gives you vectors. Unless we are the lead a/c to start with of course. The sweetest thing a TC gives us is: "Keep your speed up; you're number 1"

The next pilot that comes into the terminal airspace will say the sweetest thing is to be able to do a stabalized approach and not get driven at the airport at a high speed but to be able to fall into the traffic pattern.

The more aircraft approaching the field at the same speed, the easier it is on the terminal controller. If they have you screaming in and the 31 crawling, it's a lot harder to mix both of you into the traffic flow. The busier the airspace the more speed restrictions the further back. Imagine that same scenario of coming to the stop light but now its an uncontrolled 2 way intersection. Having cars equally spaced at equal speeds all lined up perfectly, would make it very easy to have them all go screaming through the intersection without T-boning each other. Now imagine one of the cars approaching at twice the speed, and another at half the speed, and trying to mix them into the line-up. The more variance in speed the more difficult terminal's job and every controllers job is.

This is just my take of how things work from the tower side. What you'd really need to do is talk to the YYC tower, terminal and enroute controller and let them show you how their normal traffic flow operates. What spacing/speed terminal requires from them and what spacing tower requires from terminal. CPL_ATC can probably show you a significantly clearer scenario than I just did too.

[whipline]

Thanks for the response tesox, its nice to hear the other side!! Again both aircraft were under radar control of the ACC and not yet switched over to FSS. The other aircraft wanted to do a series of practice approaches and had no intention of cancelling IFR.

I was a little miffed that we were burning gas so another airplane could practice an approach.

[bigfssguy]

Tesox, there are FSS airports in the west that are provided vectors. I was in Thompson for 2 years where the controller would space and vector aircraft to either end of the same runway. He would line them up just right to have the aircraft land and clear the runway and the other aircraft would be on a 4-8 mile final for the opposite runway.

It was amazing to watch him work it was approz 15 miles vis and cig of 500ft. We landed 15 aircraft in about 20 minutes as opposed to something like 45 minutes if he had stacked them on the NDB. I would call him on our hotline when he was on the runway, he would lower the next aircraft, then i would call him again when he cleared and the next aircraft go the approach.

Worked out great. But as a provisto to that Thompson's radar is only 6 miles from the airport and they have radar coverage down to about 20 feet off the runway.