question about runways

[Chananya Freedman]

I have an idea that I'm wanting some more clarity on.  The idea is like this:  Runways at airports have numbers like their heading and sometimes they have something that looks like this: 
Runway 29 and Runway 16
Or Runway 29 R and Runway 16R and 29L and 16L.

How do they decide whether runways have a left and a right or just regular runways?  my theory is the following: The airports that have left and right runways are usually the bigger airports.  Is that theory mainly true, except with a couple of exceptions?  For example, Tuscon Intn'l airport and Van Nuys here in LA?  Is there any information explaining how this works?

I don't know if I explained this correctly, but i did my best.  Please let me know if I'm right or wrong.  (Or should I say "right or left"?  Pun intended. 

Chananya

[djmodifyd]

parallel runways will have the R or L...

rwy 28 and rwy 10 are the same piece of concrete, just facing the opposite direction:  280 degrees, minus 180 = 100..

if you have TWO runway 28's...next to each other...the one on the left will be rwy 28L, and the one on the right will be 28R....and on the other side you will see runway 10L and 10R

you mainly see this is larger airports...because smaller airports dont usually need parallel runways because they do not require the greater capacity.

i hope this makes sense....

[tyketto]

There is a little bit more to it than that, though. I agree that it is definitely capacity related, but it may also be relative to how much land is available at the airport, let alone time-long study in weather patterns at the area in question. For example, KVGT, KHND, and 61B aren't large airports compared to KLAS, but they all have parallel runways (12L/R and 30L/R at VGT, 17L/R and 35L/R at HND, and 9L/R and 27L/R at 61B). I can guarantee you that none of these satellite airports get as much traffic as KLAS, but because of how much they get, related to land available and wind/weather patterns, they have what they have.

By comparison, KSMF has parallel runways (16L/R and 34L/R), as does one of its satellite airports, KMHR (4L/R and 22L/R). But KSAC doesn't. It has 3 different runways altogether (2/20, 12/30, and 16/34). Mostly these are related to weather patterns and capacity (in MHR's case, it is a former AFB).

You can tell number of operations at a given field (on a given day) by looking at the Airport Operational stats on the airport's page at Airnav.

BL.

[djmodifyd]

There is a little bit more to it than that, though. I agree that it is definitely capacity related, but it may also be relative to how much land is available at the airport, let alone time-long study in weather patterns at the area in question. For example, KVGT, KHND, and 61B aren't large airports compared to KLAS, but they all have parallel runways (12L/R and 30L/R at VGT, 17L/R and 35L/R at HND, and 9L/R and 27L/R at 61B). I can guarantee you that none of these satellite airports get as much traffic as KLAS, but because of how much they get, related to land available and wind/weather patterns, they have what they have.

By comparison, KSMF has parallel runways (16L/R and 34L/R), as does one of its satellite airports, KMHR (4L/R and 22L/R). But KSAC doesn't. It has 3 different runways altogether (2/20, 12/30, and 16/34). Mostly these are related to weather patterns and capacity (in MHR's case, it is a former AFB).

You can tell number of operations at a given field (on a given day) by looking at the Airport Operational stats on the airport's page at Airnav.

BL.

thanks for the addition!

[cessna157]

Now, just to add to the confusion, take an airport like ATL.  ATL has 5 parallels, all with exactly the same runway heading.....092 I believe if I remember correctly.  8L/R 9L/R and 10

[jsapyta]

Here's a little bit of more confusion. 

Here 90-100 miles north of Tucson, is Phoenix Skyharbor.  They used have just two sets of runways, 8 and 26, then about 5 or more years ago, they added another runaway to the south side.. So now you have a pair of 25's L-R and 7 R-L on the south side and runway 26 and 8 and on the north side of the airport.

And here's another confusion for you. Dulles International Airport just recently opened another runway going North-South. So now they have 19R, 19C and 19L and the opposite of them are 1L, 1C 1R.. There is no true 0 runway that I have seen. And they also have just a single going 12-30

[KSYR-pjr]

Here 90-100 miles north of Tucson, is Phoenix Skyharbor.  They used have just two sets of runways, 8 and 26, then about 5 or more years ago, they added another runaway to the south side.. So now you have a pair of 25's L-R and 7 R-L on the south side and runway 25 and 8 and on the north side of the airport.

In looking at Phoenix's airport diagram I see that the single runway to the north is 8/26 and the parallels to the south are 7/25s.



Contrary to the idea that it is confusing, I am pretty certain that the feds purposely designated the north runway differently (and in all other cases where there is a separate runway that matches the magnetic heading of the existing parallels, as in KDEN and KATL) in order to prevent pilot and controller confusion.   

[MathFox]

And here's another confusion for you. Dulles International Airport just recently opened another runway going North-South. So now they have 19R, 19C and 19L and the opposite of them are 1L, 1C 1R.. There is no true 0 runway that I have seen.

There are no 0 runways, but I know of several 18/36 runways (Amsterdam has 18/36 L-C-R). There is a rule that MAXIMUM 3 runways on one airport may have the same number (giving an L-R pair or an L-C-R trio), other runways in the same direction get another number. If two runways are close together it is custom to designate them as an L-R pair and the far-away third as a separate (avoiding confusion is worth something.)

[cessna157]

Yes, precisely.  You can have as many parallels as you want.  But only 3 in a row will have the same name.  Check out DFW.  They've got 5 parallels.

[tucraceman]

Just to clear it up...Tucson is not exactly a small airport.
~D