What Does this Instruction Mean?

[midlifeflyer]

42 minutes ago, Bob - S50 said:

carqwik,

 

I'm with you.  To me, a 3 mile base means on a base that will result in me crossing the final at 3 miles if I don't turn.  By the time I make the turn and roll out on final I will actually be just a bit inside 3 miles.

 

That is exactly the problem with phraseology with no official meaning. 

If a controller wanted me to do that I would expect the instruction to be "report

base for a 3 mile final."

[slowflyin]

A quick google search revealed a ton of links to this subject.  Many responses from controllers  state they want a 3 mile final but just as many stated they expect a base leg three miles long.    It's interesting that his has come up on so many forums.  Also, most forums had at least one person that attempted to find a regulation to support a position.  All I read reported no joy.

[Bob_Belville]

37 minutes ago, midlifeflyer said:

That is exactly the problem with phraseology with no official meaning. 

If a controller wanted me to do that I would expect the instruction to be "report

base for a 3 mile final."

In 3100 hours I've never heard anything that sounded like that. If I'm given a "report a 3 mile left base" I'm assuming the controller is anticipating he/she will be able to work me in to his/her traffic when I call in 2 minutes from touch down. I've often been told I'm #2 or #3 "following a Cessna on a 1 mile final" or similar. The tower generally will leave it to the pilot to plan his turns and the tightness of his pattern at a controlled field.

Now, at SunNFun you might have just turned downwind and hear "Mooney, left turn NOW cleared to land 9 Left on the purple dot, start your turn NOW." To which you say nothing. The controller will know you understand when he/she sees your immediate roll into a 45-60 deg bank. 

[co2bruce]

17 hours ago, midlifeflyer said:

He just wants you to report in case he is distracted, But unless he tells you to extend your downwind or that he will call your base, he's expecting a normal traffic pattern.  You need to wait for "cleared to land" in order to touch down, not in order to continue to fly a normal pattern just because communication is temporarily blocked..

so if i get to my base to final turn, turn toward the runway and continue decent to runway? If I still don't hear from tower execute a go around. This can be a busy training airport with people doing go arounds, touch and go's, taxi backs, as well as struggling with the English language. Sometimes the controller can be in a conversation with an approaching aircraft for a minute or so. The mooney covers a lot of ground in a minute, but I got my answer and in the future will fly a normal pattern and ?????? 

[N33GG]

Without knowing the details of the airport, this could be off.  However...

Frequently at airports with towers, if you are coming in more or less perpendicular to the runway, "report 3 mile base" would indicate to me they are telling you to skip the pattern, possibly for traffic efficiency.  Or for convenience.  I get this all the time at certain airports I fly in to regularly. 

Without more information, "Report X mile base" equals "Skip normal pattern (downwind)"

If in doubt, you can, of course, ask for clarification. 

And the "3 mile base" is the distance on base from the centerline of the final approach path.

Edited February 22, 2016 by N33GG

[midlifeflyer]

1 hour ago, co2bruce said:

so if i get to my base to final turn, turn toward the runway and continue decent to runway? If I still don't hear from tower execute a go around. This can be a busy training airport with people doing go arounds, touch and go's, taxi backs, as well as struggling with the English language. Sometimes the controller can be in a conversation with an approaching aircraft for a minute or so. The mooney covers a lot of ground in a minute, but I got my answer and in the future will fly a normal pattern and ?????? 

Pretty much. Don't worry about it being busy (was this KFXE on a gorgeous Saturday afternoon?). Juggling that is the controller's job. Your job is to fly the pattern, look for conflicting traffic, follow instructions that are given, and ensure your own safety. I would definitely be concerned if I saw traffic inbound on a long final and couldn't report to the Tower, but short of a situation like that, I would continue flying the normal pattern and go around if not cleared to land.

[midlifeflyer]

1 hour ago, N33GG said:

 

Without more information, "Report X mile base" equals "Skip normal pattern (downwind)"

If in doubt, you can, of course, ask for clarification. 

 

There is no "normal" pattern entry to a towered airport, just as there is no rule about left or right traffic. It is whatever Tower instructs you to do. It could be straight in, base entries, close-in downwinds, wide downwinds, overhead crossing, circle 3 miles from the airport waiting for a slot to open, and extended versions of all of those (I think I've heard all of them and a few more during my 20 years at Denver Centennial -KAPA)

The bottom line is, of course, to ask for clarification of any instruction you don;t understand. It makes good sense and it's even a rule.

My person preference for clarification in general is to read back my interpretation of what was said. So in this case, if I were confused, in response to  "report 3 mile left base" I would read back "Report left base 3 miles from the airport."

[Hank]

If I'm told to report a 3-mile base, I'll orient myself perpendicular to the runway around my normal base-leg distance out, and let him know when I'm 3 miles away. If the controller wants me to turn final 3 miles from the threshold, he should ask me for a 3-mile final. I've been given both, with various distances, and this is always how I've handled it. ATC asks for base leg entry at X distance, I line up for base leg and call at X; if ATC asks for Y-mile final, I maneuver around to final and call in when Y distance out.

My first "report 6-mile final" was as a brand new pilot, flying my new-to-me Mooney, going to a MAPA PPP. Didn't really know what to do, hadn't really done m any straight ins and never at an unfamiliar field, so I gave it my best shot. I think I hit pattern altitude around the 6 nm point, aimed towards the runway [sort of], flew in and landed with no complaints from the tower.

[midlifeflyer]

Just now, Hank said:

If I'm told to report a 3-mile base, I'll orient myself perpendicular to the runway around my normal base-leg distance out, and let him know when I'm 3 miles away. If the controller wants me to turn final 3 miles from the threshold, he should ask me for a 3-mile final. I've been given both, with various distances, and this is always how I've handled it. ATC asks for base leg entry at X distance, I line up for base leg and call at X; if ATC asks for Y-mile final, I maneuver around to final and call in when Y distance out.

You and I would fly this instruction exactly the same way.

[carqwik]

I called the tower this morning for clarification.  The gal tells me that this is an instruction not found in the AIM...but what is meant is that I should fly a normal base leg (e.g., where'd you normally turn base) and the 3 mile instruction refers to the distance from the threshold that you should report.  It does not mean fly a three mile final...at least not at DVT.  She said that when they want you to fly a specific final leg, the instruction would be "join final at X miles."  So now I know...

Btw, I even think she knew about why I was calling when I asked the question referring to yesterday's scenario...she seemed to be aware of it and said I really didn't do anything wrong.  She was very nice. 

[carusoam]

I like that you called the tower to follow up and communicated the details with us!

Go MooneySpace!

Best regards,

-a- 

[Jeff_S]

At the risk of not having much to add, I'll pile on anyway (slow day at the office). We get similar instructions like these at KPDK all the time. As has been noted, there's really no way to perfectly determine whether you're on a 3 mile base leg, 3 mile final (well, that's easier) or 3 mile hypotenuse. And I can't image they care that much. It seems to me it's really just a quasi-clearance, almost like an IFR reporting point, so they can keep track of people and know generally where to look. Because at least at my towered field, the radar isn't really what they go by at that point...they have binoculars and they are looking for you out the windows. I know this because we just had a controller-pilot seminar last week and this is what they told us.  (Aside for anybody who's ever flown into PDK and heard the lilting, almost musical ATIS renditions of Phillip the controller...he's the best!)

The other issue the OP mentioned was the dissatisfaction the controller expressed with his original reporting point. While it is true that local landmarks are often used (here it's the King and Queen building), if there a lot of students in the area they may not really  know what that means. So in order to help them maintain situational awareness, it probably is a better idea to give a more thorough reporting point. After all, you're talking to the other pilots as much as the tower...or they should be listening, anway!  It's no different than practicing approaches on a nice VMC day...none of those VFR pilots have any clue where AABEE or CHAMB are unless you give them some distances from the airport. (And yes, I realize you would never be on that approach without ATC clearance...it was just an example.)

[midlifeflyer]

Just now, Jeff_S said:

The other issue the OP mentioned was the dissatisfaction the controller expressed with his original reporting point. While it is true that local landmarks are often used (here it's the King and Queen building), if there a lot of students in the area they may not really  know what that means. So in order to help them maintain situational awareness, it probably is a better idea to give a more thorough reporting point. After all, you're talking to the other pilots as much as the tower...or they should be listening, anway!  It's no different than practicing approaches on a nice VMC day...none of those VFR pilots have any clue where AABEE or CHAMB are unless you give them some distances from the airport. (And yes, I realize you would never be on that approach without ATC clearance...it was just an example.)

You make a great point on a side-issue in the thread. Local landmarks (as opoosed to charted reporting points) as reporting points are common. .

But it's not usually a cause for Tower criticism (unless the controller was new to the airport) since Tower uses them as much as pilots do. We had a bunch of them around KAPA, coming in from all directions.

Most of the problem comes from transient pilots when Tower instructs "report [Local Landmark]" and the pilot has no clue. But like most other things of that type, the answer is simple. There are two "U" words every pilot should know when dealing with ATC. One is "unable." The other is "unfamiliar."

[N33GG]

23 hours ago, Jeff_S said:

 As has been noted, there's really no way to perfectly determine whether you're on a 3 mile base leg, 3 mile final (well, that's easier) or 3 mile hypotenuse. And I can't image they care that much. It seems to me it's really just a quasi-clearance, almost like an IFR reporting point, so they can keep track of people and know generally where to look.

Absolutely!  All of this nonsense started with the advent of GPS.  In the good old days, a report was more like "report about 3 miles out", "N123XX about 5 mile north", etc.  And it all worked fine.  Back then, pilots spent a fair amount of time figuring out ways to make pretty good estimates of distance.  Then, when GPS came around, it was "N234MM 5.3 from airport", "N456HH 3.1 north", etc.  You could tell who did and who did not have GPS for some time.  Now, everybody is worried about the tenth of a mile.  What's next???  While I appreciate precision, we aren't building cabinets here.

Kind of reminds me of a mechanical engineer or two that used to work with me, and they always wanted to spec and do everything to the maximum precision available.  Excessive precision is not always a good thing.  You have to know when enough is enough. 

[jlunseth]

You guys that think "3 mile left base" means 3 miles perpendicular to the final leg, just exactly how do you measure that??  Is that out over the lake NW of the airport?  Well, that's great if you know the airport but what does someone do if they are unfamiliar and they get that instruction.

3 mile left base means come in on a left base and report when 3 miles from the airport.  It ain't even 3 miles from RWY, cause how are you going to measure that unless you put in an approach and hit direct->direct RWY.  I would report when my GPS says 3 miles, and that is going to be 3 miles from the center of the airport because that is where the waypoint is.  Remember, they can see you, they have your transponder, they just want you to bug them to give you a clearance in case they have not done it yet.

[peevee]

report 3 mile anything just means they want to know when you're about 3 out so they don't forget to clear you to land. here normally if no traffic pops up they'll clear me to land and delete the restriction before I get there... if it's a VFR tower and they don't have a d-brite type device they don't know where you are and can't judge 3 miles from 5 visually anyway. If they do have radar.... they likely don't care that much.

Remember, all a VFR tower is responsible for is that strip of asphalt. Not the airspace around it.

[MyNameIsNobody]

On February 21, 2016 at 2:29 PM, Mooneymite said:

I would go with drawing #2.

However, I suspect a call three miles from the approach end of the runway would mollify "most" tower controllers.

DVT?  Who knows.  That place is a zoo.

 

I see two drawings.  One is on top of the other.  I don't see numbered drawings...

Original poster, does that sound like your controller?

He is/was a D.I.C.K...

[Bob - S50]

I posed the question over on Beechtalk and got conflicting answers there, even from ATC controllers.

I've come to the conclusion that since there is no defined standard, I'm going to ask for clarification.  From now on, if they ask me to "report a 3 mile left base" my response will be something like:

"For 1CB, by 3 mile base do you mean base for a 3 mile final or on base and 3 miles from the runway?"

Bob

[Mooneymite]

25 minutes ago, MyNameIsNobody said:

I see two drawings.  One is on top of the other.  I don't see numbered drawings..

Yes, the lower drawing I called #2.  Like I said, with the GPS set to threshold, just report 3 miles from that and the tower can't  squawk too much....

I suspect the controller is more interested in time/distance to runway than how long your final is.

(GPS to threshold....not airport)

Edited February 24, 2016 by Mooneymite

[slowflyin]

4 hours ago, Bob - S50 said:

I posed the question over on Beechtalk and got conflicting answers there, even from ATC controllers.

I've come to the conclusion that since there is no defined standard, I'm going to ask for clarification.  From now on, if they ask me to "report a 3 mile left base" my response will be something like:

"For 1CB, by 3 mile base do you mean base for a 3 mile final or on base and 3 miles from the runway?"

Bob

2

This was my experience.  No real consensus even among controllers.   Some folks are adamant their opinion is correct, but in the end, it seems there are only opinions.  I can't seem to find any regulations to back this one up. 

[Bob]

On ‎2‎/‎22‎/‎2016 at 11:59 AM, carqwik said:

I called the tower this morning for clarification.  The gal tells me that this is an instruction not found in the AIM...but what is meant is that I should fly a normal base leg (e.g., where'd you normally turn base) and the 3 mile instruction refers to the distance from the threshold that you should report.  It does not mean fly a three mile final...at least not at DVT.  She said that when they want you to fly a specific final leg, the instruction would be "join final at X miles."  So now I know...

Btw, I even think she knew about why I was calling when I asked the question referring to yesterday's scenario...she seemed to be aware of it and said I really didn't do anything wrong.  She was very nice. 

Sounds like the controller was having a bad day, then pacing the tower and complaining.  Then the "gal" overheard him, then you called and she helped smooth it out for him and remove unknowns for you.  DVT is beyond a high work load challenge.  The 30 students in the air with translators (instructors) sure does push it to the next level for everyone.  The upside is, if you fly into DVT a few times, you will be trained "strong" and everywhere else will be reduced workload, even OSH!

[NotarPilot]

I've been taking an Aviation S.M.S. course put on by U.S.C all week. Today we discussed communication as it relates to safe aircraft operation and numerous examples of miscommunication between crew, ATC, maintenance, etc were used. Examples of miscommunication which ultimately lead to several disasters. That being said many changes were made over the years on how we communicate in the aviation industry especially with ATC. Read about the Flying Tigers flight 66 or Tenerife disasters as good examples. Perhaps you should consider filing an A.S.R.S. report to bring this issue to light of the safety people. Not to get anyone in trouble but to show that this is an issue and perhaps standardized terminology is needed. Just my two cents.

Aviation safety reporting system

[Guest Mike261]

reporting entering a 3 mile left base doesn't work if you base the position on intersecting a 3 mile final.

if you look at the drawing of Podunk airport i attached you can enter anywhere on the base leg as depicted by the black arrows, any of these places would be considered a three mile base using this convention. this doesn't give the controller or anyone in the area an idea of your position. you could be outside the 5 mile ring and be on a three mile base. 

 

if you report 3 miles out on a normal base, your position is pretty well known. a controller i know says back in the day they assumed you were reporting distance from the airport reference point on a sectional, but these days with gps its tacitly understood to be the threshold. either gives a more accurate indication of position than the other way.

that's my story and i'm stickin to it.

mike

[flyboy0681]

On 2/21/2016 at 3:37 PM, 201er said:

Or #3, 3 mile hypotenuse (direct to airport) distance while on base leg.

I vote for this one. 

[Guest Mike261]

Here is published advise from the FAA control tower at aurora municipal airport in illinois: their bold emphasis not mine. linky:http://www.auroraairport.com/businesses/tower.htm

8.  Give the Tower accurate position and distance reports. Pattern entry and landing sequence are based on your reports. To aid you and the Controller, become familiar with local reporting points (as shown on the Chicago VFR Terminal Area Chart). Enter the traffic pattern at the position the Tower instructs (base, crosswind, downwind). If unable to do so, advise. Base all distances from the middle of the airport.