Sign in to follow this  
baw716

BAW716-First Flight Observations

Recommended Posts

I must first say that the patch has made a world of difference in the performance of this aircraft, so my congrats to PSS. You've taken a lot of heat, but I think the patch you developed has solved 98% of the problems that I have read reported and that I have experienced myself.The flight was KSEA-KMLW, FL250, dep off 34R, BLUIT4, EPH then over top MLW, right base ILS 32R. Flown offline with no ATC. MCP setup before runway, A/T armed, SPD V2+20 (147), HDG SEL, altitude 25000ft. LNAV out of 5000ft (and DME SEA 5.0), VNAV out of 10,000ft.No problems with CDU setup; however, had some difficulties getting rid of DISCOs. I read the PSS manual and then the FMC Guide and discovered that it is not possible to remove DISCOs in this FMC on the real 777 and that LNAV will continue to hold track after the DISCO. Since I am learning this airplane as I am flying it, that certainly was an interesting (and somewhat frustrating) experience. That said, there are ways to work around it and in some cases, the DISCOs are an advantage (acc FMC Guide), although I have yet to find them.Departure was spry (next to no payload and little fuel), so the thing climbed like a rocket. Flew by hand on FD to 220kts (flaps up), then engaged (in order LNAV, VNAV, A/P). All were confirmed on the FMA on the PFD.First concern: The LNAV was a little slow to capture the first turn; in fact it was late at the turn and at the next turn at the next waypoint. I intentionally let it go to see how it would perform. VNAV captured FL250 spot on, but I noticed I could not hold a 280kt climb to FL250 (step size 0), it was off by about 8-10 knots, even with a 20kt tailwind.Second concern: VNAV captured the speed change at the top of descent but did not capture the altitude I had dialed in at the TOD. I flipped over to ALT HOLD and FLCH to initiate the descent, then reverted back to VNAV (I am not certain procedurally this is correct to do, but it accepted it). I crossed MLW at 8400 feet, which was the altitude dialed into the FMC based on the descent profile setup at SEA. The only other problem I had was that because of the steepness of the descent, the a/c would not hold 280kts; I was on the speedbrake a good portion of the way down (again, I think this is technique rather than the aircraft).Third concern: When I got to MLW (the point of the DISCO), the aircraft initiated an uncommanded left turn. I scanned things to assure that I nad not done something and checked the FMC to check the course dialed in for after MLW (140). From then on, I operated in HDG SEL and SPD/FLCH and V/S for the remainder of the approach.There was one unusual event on the CDU: On the DES page, there were some odd characters in white on the screen which did not belong. While I was not in VNAV at the time, it was distracting, as I was turning to final and verfying Vref+5 (on the approach page).The a/p captured the G/S perfectly; however, it did not initiate descent. I had 3000 dialed into the FMC after the G/S capture, to set up the g/a altitude, but did not arm it. I then attempted to disconnect the A/P and it would not disconnect (however, on reflection I think this was pilot error, not the aircraft). I was able to get the aircraft back down to the glideslope by pushing the yoke down hard and once back on the needles, performed a full autoland. Thrust did not idle at touchdown, I had to kick out the a/t and give the throttles a quick up and down to throw the engines into idle. Reverse thrust did not work either (this probably is joystick programming related). The aircraft was spot on the centerline all the way to the end of the runway.On the ground, I noticed the aircraft had a tendency to veer to the right during straight taxi...plus there was a slight uncommanded increase in power (I need to check the sensitivity of the throttles as well).Parking at the gate fine, shutdown and power conversion to APU without incident.Observations (possible PSS issues)-Slowness of capture of turns in LNAV (on reflection, rate of climb may have had an impact..it was >5000 fpm)-unable to resolve DISCOs (I think this is just the way the FMC is).-speed loss in VNAV CLB with a/t engaged and 20kt tailwind.-VNAV did not initiate descent at TOD.-uncommanded left turn at MLW VOR (turn should have been to the right).-G/S capture (and annuciated on PFD), but no descent initiated.-unable to kick out a/p (this one very well could be pilot error..aargh)-on PFD, the correct g/s identifier was displayed, but no other information (e.g. distance from).-a/t did not command idle thrust at touchdown.-slight uncommanded increase in power during taxi (probably joystick related).Notes: I was very careful in setting up the flight (used load editor, fuel calculator, consulted FMC Guide and PSS manual to assure I was entering correctly). That said, I am reasonably certain some of this is pilot error; however, if Norman or Steve, if you have some questions to push back my direction based on my description, we may be able to ferret out what is mechanical and what is not.All in all, I am very pleased with this aircraft. If anyone has any other questions, comments or suggestions, I would greatly appreciate it.Many thanks,Dave LambComputer setup:Custom build AMD Athlon 64 (2.0ghz) not overclockedNvidia motherboard, 3GB RAM (DDR3200 Dual Channel)Disc drives: C: 250gb (85% free), D: 125GB (84% free)Video Card: Nvidia GeForce FX5200 256mbSound Card: Creative Sound Blaster 5.1 DolbyInternet: FAST broadband (7000mb+ down)

Share this post


Link to post
Share on other sites
Help AVSIM continue to serve you!
Please donate today!

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this