Saturday, October 30, 2010

Phoenix - Los Angeles / Boeing 737-700 (SWA2406) / IFR

Lots of flights have come and gone, and as usual I've been too lazy to log them all, but some have been more interesting (and thus more “loggable”) than others.

This flight was a mirror of the real world Southwest Airlines Flight 2406, from Phoenix to LAX. As usual, my mirror was nearly identical to the real-world flight. Inevitably some discrepancies creep in, but I'm always impressed by the extent to which the simulated 737 tracks the performance of the real thing.

There are some compromises, of course. I fly a 737-800, whereas the Southwest flights are usually 737-300s or 737-700s—Southwest is thinking about acquiring 737-800s, but it hasn't actually done so yet. And at my end, I've only installed PMDG's 737NG aircraft, which gives me a 737-800s and 737-900s. I fly the -800 but I log on as the real submodel for the benefit of other simmers on the network. The performance is different, of course, but not enough to be a big issue.

This flight went swimmingly. As always, the greatest challenge of the flight is to get airplane back down on the ground (as in real life). I like to restrict the FMC airspeed in the descent to 280 KIAS, because it seems to make it easier to stick to the descent path, although it makes the flight a tiny bit longer. Energy lost before or early in the descent is energy I don't have to shed as I struggle to finish the arrival and start the approach.

Still, the FMC occasionally complains and sometimes kicks me out of VNAV with the dreaded DES PATH UNACHIEVABLE. If I'm unable to avoid this, I switch to V/S and adopt my own, somewhat more aggressive descent path until I'm back on the FMC path. It works pretty well. One thing I don't know is how closely these nuisances match the real aircraft. I know that some real airliner FMCs have trouble following a descent path, too, but I don't know if the 737-800 FMC is better or worse than my simulator's version thereof.

I was a bit spooked during my approach. ATC was offline, putting me in the highly unrealistic position of announcing on CTAF for LAX. I dutifully made my announcements, but not everyone was so diligent. Less than 20 miles out, another pilot advised me that he was in front of me, heading for 24R, just like me. Sure enough, a glance at the TCAS showed traffic ahead, closing fast. He assured me that he was at 140 KIAS in his airliner, and I was slightly above, but even after slowing I soon could see him very clearly in front of me, no TCAS needed. Finally I decided to side-step to 24L with his tail rapidly looming larger in my windshield. This entailed hand-flying the rest of the approach and landing, but I surprised myself by doing very well, with a smooth landing, although I landed a little further from the threshold than I would have liked.

This quick maneuver was exciting in a way, but stressful too. Rattled as I was, I turned at the wrong place at Terminal 1 and didn't park at Gate 13 like I was supposed to. Oh well. At least I averted tragedy.

When ATC is online, of course, this doesn't happen, since we are all coordinated by controllers. I suppose in a sense it's impressive that traffic to LAX doesn't all end up in a twisted mass of virtual metal when ATC is offline, because sometimes there's a lot of traffic.

Despite the excitement, I arrived at the gate at about the same time as the real-world flight.