Route Clarification for KLAX

[CaptainMD]

Hello PE,

In planning a flight from KPSP to KLAX, PEaware advises the following route CATH1 PSP V388 LENHO SEAVU SEAVU2 based on most flown.

Where it says SEAVU SEAVU2 in the route, does that mean after LENHO, fly direct to SEAVU or Expect to fly the entire SEAVU2 STAR starting from Thermal TRM as published in the SEAVU2 arrival description in the plate ? It seems odd to backtrack all the way to TRM after PSP.

Thanks in advance

[rtataryn]

LENHO direct SEAVU.

TRM is not part of the arrival. Perhaps you mean TNP. No. The route does not include the TNP transition. That’s TNP.SEAVU2.

[CaptainMD]

Thank you! Yes, I meant to write Twentynine Palms TNP instead of Thermal TRM.

I was confused as to why SEAVU is before SEAVU2 when SEAVU is already part of the SEAVU2 arrival. I was of the understanding that when a STAR is part of your cleared route, the expectation is to fly the entire path of that STAR as written in the plate routing instructions. Why bother putting SEAVU2 if direct SEAVU? FlightAware has the same route too.

[rtataryn]

Filing just SEAVU would be the same route, but if you were assigned the SEAVU TWO in your clearance then the crossing restriction at SEAVU would apply. I’m not sure if there would be any other purpose for ATC to assign it, or any reason to file it.

[Ray Salmon]

In addition to being able to give you a “descend via” clearance triggering the crossing restriction, the arrival also specifies which approach to fly in the event of lost comms. That would be the only other reason I could think of for them to assign the arrival to you in this case.

[Shawn Goldsworthy]

The only reason I can see that the SEAVU2 is on that TEC route is for lost comms purposes, where is says to proceed via the KLAX ILS 25L. The actual STAR ends at SEAVU, so you are ultimately flying 0% of the arrival.

That said, there used to be transition routes from SEAVU to each individual runway. Those aren't there anymore and the TEC was never changed.

[CaptainMD]

Wow, great discussion guys! I think I got it.

So because they put SEAVU2 after SEAVU in the route, it triggers the altitude restriction at SEAVU between 14,000 and 12,000 feet and lost communications instructions. Otherwise if it was just SEAVU, one could cross at whatever their attitude is at that point in time.

If they did not put SEAVU in front of SEAVU2, the expectation would be to fly the entire STAR starting at TWENTYNINE PALMS TNP.

Thanks!

[Ray Salmon]

Wow, great discussion guys! I think I got it.

So because they put SEAVU2 after SEAVU in the route, it triggers the altitude restriction at SEAVU between 14,000 and 12,000 feet and lost communications instructions. Otherwise if it was just SEAVU, one could cross at whatever their attitude is at that point in time.

If they did not put SEAVU in front of SEAVU2, the expectation would be to fly the entire STAR starting at TWENTYNINE PALMS TNP.

Thanks!

Actually, in looking at it closer, even the crossing restriction is moot. The TEC route altitude is 12,000, so you're already at the bottom altitude for the arrival. Looks like lost comms is the only reason, like Shawn said.