Midway 3

[sellener777]

I have yet to hear an explanation that makes sense to me on this departure. I flew it once years ago and forget how it went for me, other then I believe i was given to departure so quick and they gave me a heading to fly so quick that the procedure wasnt really flown.

But does anyone else find it confusing specifically departing RW 4L/R?

Suppose I was cleared via midway 3 climb via sid.....


If i remember tower gave me a heading with takeoff clearance, then slight confusion Occured.

Not sure about local procedure between tower and approach but...

Either tower clears u for takeoff without heading or with a heading.

If tower doesnt assign heading it makes sense.

If however which i believe is what occurs, tower gives u " fly heading xxx runway 4L cfto, i am a bit confused.

1) what if tower assigned heading 270.....i read it as fly 270 and make turn south of the radial. (No turn to 100)

2) what about tower assigned 020 with takeoff clearance? Then i read it as you dont really fly that heading untill u complied with DP. That is where most of my befuddlement occurs. Not used to getting a "fly heading 020" from tower but not flying the heading.

I also get confused on this one with the phrases of "complete initially assigned turn". Are they referencing te tower assigned heading or the dp heading 100? I assume the tower heading cause other runways dont have a turn depicted on dp.

And on this one spexifically i am confused with the phrase of "proceeding on course", as it reads for 4L/R . Are they speaking about the tower assigned heading or some other course? I would have expected something more of "climb right turn to 2400 heading 100 then via tower assigned heading"

Ideas?

[sellener777]

Also maybe i uave confusion with what an "assigned heading" is in the dp text.

Ie is it referencing an assigned heading in the clearance itself? (i dont remember if clearance gave one). Or is it referencing a tower assigned heading? Or is it referencing the headings depicted on Dp?

It also seems strange that you would have no way to brief the dp with knowledge of the "assigned heading" which i didnt get untill my takeoff clearance which makes me curious if im confusing an "assigned heading" givin with my initial clearance and a tower assigned heading on takeoff?

Perhaps im making this difficult. If tower says fly heading 020 4L cleared for takeoff i would normally understand that but with the dp and obstacles to the NW i am still confused.

[RyanK]

Agreed that it's confusing. From the 4s, I interpret it as an initial 100° heading to 2400, then a turn "on course" to the assigned heading, followed by vectors to the first enroute fix. The "initially assigned turn" referred to in the DME/Non-DME section would have to be the turn to 100. That's the only way it makes sense to me.

[jx_]

Hey E.,

It means do not turn from heading 100 until either 1) non radar at or above 2400 feet or 2) RADAR contact & receiving ATC RADAR vectors.

Problem is the phraseology they are using, 'climb XXX heading to XXXX', hasn't been formalized and the phraseology "Fly Heading" should normally cancel the non-radar lateral path. The intent here is to save the controller from saying "fly heading 100 until 2400 feet then fly heading 270".



here's how it works.

Fundamental rules that take precedence for this conversation:
1) the last ATC clearance issued has precedence over the previous, the phraseology “maintain (altitude)” alone cancels previously issued altitude restrictions, including SID/STAR altitude restrictions, unless they are restated or modified.
2) when the airplane is under radar navigation (not on a published routing) it must have an ATC assigned altitude to maintain.

AIM reference -
5-2-8

4. (Using the Example 3 flight plan, ATC determines the top altitude must be changed to FL180). The clearance will read:
“Cleared to Johnston Airport, Scott One departure, Jonez transition, Q-One Forty-five, Climb via SID except maintain flight level one eight zero.”

NOTE−
In Example 4, the aircraft must comply with the Scott One departure lateral path and any published speed and altitude restrictions while climbing to FL180. The aircraft must stop climb at FL180 until issued further clearance by ATC.

7. If prior to or after takeoff an altitude restriction is issued by ATC, all previously issued “ATC” altitude restrictions are canceled including those published on a SID. Pilots must still comply with all speed restrictions and lateral path requirements published on the SID unless canceled by ATC.

So you're on the ground at MDW and ATC clears you "Midway Three departure, Gippur, then as filed. Climb via SID except maintain 3000......"

In this case you 'must comply with the Midway Three departure lateral path and any published speed and altitude restrictions while climbing to 3000'

You reach tower, and tower says fly heading 180. This does not cancel your altitude clearance of Climb via SID except maintain 3000, he must assign an altitude to maintain to cancel the climb via. If he doesn't cancel the climb via you're not supposed to turn until 2400 because in this case the lateral path is conditional upon the altitude; but the instruction to "fly heading" should cancel the Midway DP entirely. For this reason it is confusing, contradictory, and unclear the way the instruction was given in your example. I would ask for clarification.

For clarity, a controller should say something like
- Midway Four departure, Gippur, initial heading 270, then as filed. Climb via SID except maintain 3000.
- or tower could say "at 2400 fly heading 270, Runway 4L cleared for takeoff." The maintain altitude for the vector portion is published on that chart.
- or the chart would need to be changed to read "Climb heading 100° to 2400 before turning, thence. . . . . . . . fly assigned heading, expected RADAR vectors to first enroute fix."

In any case, if you see 'climb heading--to' and are given climb via SID, don't make any turns from the charted heading unless either 1) non radar at or above the altitude restriction or 2) RADAR contact & receiving ATC RADAR vectors.


See BFL MEADO3 DP & LGB ANAHM9 DP --- Same deal, but they are so confusing in their present state LGB won't use them.



Assigned heading is the tower heading. Also called initial heading and 'on course'. Yes it's poorly worded!




The reference to the DME/Radial is for vertical planning. You have to reach the turn altitude (2400 RWY4) before you hit the constraint DME/radial. For example - Departing 31L : Climb heading 318° to 1500 before turning, turn before 4DME/DPA096; climb/maintain 3000. Your turn to the charted heading starts at the standard 400 feet or end of runway unless otherwise depicted.




Hope this helps.

JX

[sellener777]

Thx all,

Good explanation JX appreciate everyones time.

Happy new year.