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w6kd

Is stable accelerated flight a PMDG 777 design criteria?

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Given the extremely long legs on a B777, it's hard for me to imagine most simmers taking on a 15+ hour flight in real time. For many add-ons, accelerated flight is a nice-to-have...seems that with this type of aircraft it's a must-have. I do note that the NGX is rock stable in 4x and 8x accelerated flight--not sure if that's by design or just a happy accident.

 

Is stable accelerated flight a PMDG design criteria for the 777?

 

Regards

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If the PMDG B777 indeed uses the coding architecture and systems logic of the PMDG B737, I would assume so, but would personally prefer real-time short-haul flights of less than two hours.

 

I agree, though, that there are times when time acceleration and deceleration are desirable. I found out the hard way that the PMDG B747 does not respond well to time deceleration (autopilot-induced stall and unresponsive elevators leading to a crash at a speed faster than the speed of sound). . . .

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taking on a 15+ hour flight in real time

 

Bring on ATL-JNB.

 

Is stable accelerated flight a PMDG design criteria for the 777?

 

I think that if the fuel and autopilot systems on the MD-11 and 744 can maintain themselves at x8, then I don't see why the 777 can't.

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I'd hope so. Even though I don't usually have time for a full real-time ULH, I don't want to be restricted to unrealistic Short hops, hence, 4x accel.

 

I haven't even completed a full flight yet in a certain well-publicised A320 because of the same thing. The most I've done is a 20 minute hop which had a CTD on finals

 

The less-publicised, often criticised 'prologue' Bus has no issues, and is silky smooth at 4x

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I don't want to be restricted to unrealistic Short hops, hence, 4x accel.

 

I haven't even completed a full flight yet in a certain well-publicised A320 because of the same thing.

But there are numerous real-world short-haul B777 flights, perhaps not frequently with the B777-200ER/LR, but certainly compatible. Take a look in Asia or perhaps Europe. In any case, using an A330, A340, B747, or B777 for an appropriate, properly managed short-haul flight is more realistic than using time acceleration.

 

The same is even more relevant to the A320. There seems to be little need of using time acceleration on the vast majority of A320 flights.

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If the PMDG B777 indeed uses the coding architecture and systems logic of the PMDG B737, I would assume so, but would personally prefer real-time short-haul flights of less than two hours.

 

I agree, though, that there are times when time acceleration and deceleration are desirable. I found out the hard way that the PMDG B747 does not respond well to time deceleration (autopilot-induced stall and unresponsive elevators leading to a crash at a speed faster than the speed of sound). . . .

 

Try putting the sim on pause, then switch back to 1X, then unpause. The 747X does fine if you work it that way.

 

I, too, would suspect that the 777 might be fine at 8X...was just wondering if it was something the design team is intentionally baking into the cake.

 

In any case, using an A330, A340, B747, or B777 for an appropriate, properly managed short-haul flight is more realistic than using time acceleration.

 

w/r/t realism...a 777 on a short-haul flight doesn't behave like a 777 loaded to the gills taking to the air for a 17 hour flight. I do that with the MD-11, for example...take it into the air heavy, do the boring overwater cruise at 8x, and then work the descent and landing in real time again. An entire day of droning isn't an acceptable price for the realistic feel of a heavy departure, IMHO. I have thousands of hours of r/w experience cruising in a heavy jet over the ocean. It's not part of the flying experience I care to re-live all that much. Both the short-haul in real time and long-haul with acceleration scenarios have a legit place in the simmer's quiver.

 

Regards

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Man up! LOL! I've only done 12 hours on the sim before, it was pretty fun and enjoyable. OMDB to the West Coast will be one of my first flights I'm the 777! I haven't done long haul since I bought the NGX last summer )-:

 

But then not everyone has my free time, neither will I from September/October )-:

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My first flight will probably be ORD-MIA or down to DFW, after that I'll be flying my usual routes with a pond hop maybe once every month or so.

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I've done DFW-NRT and LAX-HKG numerous times at 1x. Sometimes I find it fun, but I treat it like a real flight and let the other crews; otto1 and otto2 fly.

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I can't imagine using time acceleration!

 

I like to simulate real world aviation, you guys could try a combat sim; you get to fly aircraft really fast there

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any "acceleration" must mess up your weather anyway ... realtime or historic.. though you can resequence historic if you use ASE / AS2012.

 

for example, you won't arrive to dawn fogs if your many hours early !!!!!

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I'd feel extremely guilty for speeding up my flights.

I usually fly on VATSIM as well which is a major no-no, these things help immerse me in realism.

One thing I do, is Take 30min breaks throughout the flight, which is perfectly acceptable while connected to VATSIM, once reported.

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If you work from home mostly, doing a 16 hour flight is a great way of getting work done :lol:

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Time compression is a bit of a lol for me. I fly on Vatsim most of the time, so I'd rather stick it out in 1x. Real world weather (AS2012) etc.

 

For me a long haul is about 2 hours of high intensity planning (about 1 hour before pushback, and then the first hour of flight) followed by periodic monitoring (pre-planned periods with alarms set for each action) till approaching top of decent (which keeps me at the cockpit for the next ~40 mins till the engines are shut down.)

 

Planning includes inserting Forecast Winds into the FMS after established at initial cruise altitude. With this information, the FMS predictions regarding waypoint crossing times and fuel burn are more accurate. This in turn means the time till step climb is more accurate from the FMC, and fuel burn to waypoints is more accurate. From fuel burn to waypoints, you can build a good picture for when fuel pumps and tanks need to be managed (MD11 doesn't need to be managed. Just stick it in "Auto" and forget. 747 needs lots of management.)

 

Once you have this sorted out you just need to set an alarm for the next "action"

 

Actions are Fuel burn, time, FIR boundary based and include: Timing FIR Boundary crossings (Useful if on Vatsim to check for ATC), fuel configuration changes & Step climbs, and generally being "within earshot" of the aircraft lets you deal with any unforseens. (TCAS alarms, autopilot disconnects, sudden extreme changes in engine thrust etc are things you can hear from a few rooms away).

 

It takes about 7 or 8 hours to cross the Atlantic (Eastern USA to Western Europe via NAT's).

10 to 15 across the Pacific (USA to Australia or Asia)

About 10 to 13 from Europe to East or Southeast Asia.

 

At best I usually can manage 2 a week (usually done on Vatsim at the beginning of a weekend ie Friday Night, Saturday night equivelent, leave Sunday for short haul or doing something out of the house.), sometimes I will only do one longhaul a month or less even depending on my mood/what needs doing.

 

Once you pass the 2 hour mark after takeoff, the only ongoing requirements at the aircraft are ATC related. This is why I prefer oceans, where Position reporting comes into effect (Procedural non-radar airspace) and ATC is less likley to randomly call you. Being passed into SELCAL watch turns ATC requests into an alarm too. Turn the ATC radio down, and only turn it up again when ATC wants to talk to you (SELCAL recieved or in response to your outgoing position report, which you obviously set an alarm for the last time you did a position report.)

 

The good ol' watch alarm. Sleep and sim. (or do housework and sim, or watch TV and sim, or browse the internet on a second screen and sim).

 

By sticking to the timetable (set an alarm, respond to it.) and doing all the tasks you need to do on time, you will reach your Top of Decent with the FMS all programmed, MCP set for decent, alarm set so you are back in the pilot seat, and then you can spend the last 30 or 40 minutes of the flight getting ready to land the thing.

 

The things that need to be done are: Checking your FS time matches your "watch time" (or phone time if using that kind of alarm).

Checking the waypoint you want to do something at in LEGS (or equivelent) page and see what time you pass that waypoint.

Set an alarm for that time (+ or - a minute or 2).

 

The hardest one to work out is the Fuel Tank-Engine feed for the 747-400. It may include making a fuel-burn chart which is time based then setting alarm for T-10 minutes or whatever before you approach 52 tonnes.

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The 747-400 certainly does need more management. However estimating when tank to engine switch will be isn't hard. I look at how much more fuel is in the inboard tanks than the outboards, divide that by total fuel flow, and that gives me an estimated time in hours until the switch.

 

It's not a problem if you miss the switch, as you can take fuel from the outboard tanks only for a while.

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QTR flies their -200LR's and -300ER's to OMDB. It's only a 30 minute flight.

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My first flight will probably be ORD-MIA or down to DFW, after that I'll be flying my usual routes with a pond hop maybe once every month or so.

My first flight will be something short, such as EGKK–LSGG, even though the B777 is not used for this flight in real life.

 

QTR flies their -200LR's and -300ER's to OMDB. It's only a 30 minute flight.

When I really lack time, I fly the B747 on LSZH–LSGG. I believe the time required to complete ground operations is greater than that of the actual flight (approximately 25 min). Nevertheless, it is extremely fun, as the manual-to-automated flight ratio is about 1:4, and there are constantly actions to perform.

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There have been several threads with shorter flights in the 777.

 

Remember:

Just because it is large, or has the capability to fly longer routes, doesn't mean that it always does.

 

The issue isn't so much the coding of the 777 as much as it is the ability of your computer to do its number crunching. Think of it this way: you're given 30 seconds to run a complex calculation, and then you must recalculate it all over again. Then, someone randomly takes that away and only gives you 5 seconds to run that same complex calculation. At some point, you're going to get overloaded and start to drop the ball. If those calculations are driving the stability of something and they start to get screwed up, then things start to get unstable.

 

For what it's worth, take your system and try and run the default Cessna on AP with time acceleration, and then keep upping the rate. Your max rate will be different from the next person's, because each computer can only handle so much.

 

Time acceleration is the worst thing anyone has ever added to the sim. If you can't fly it, don't fly it. That goes for weather, route length, route complexity, or aircraft type.

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Time acceleration is the worst thing anyone has ever added to the sim. If you can't fly it, don't fly it. That goes for weather, route length, route complexity, or aircraft type.

 

I must disagree. I don't regularly have time to do a 12 hour leg. I still enjoy planning the entire flight (fuel, w/b, wx etc). There are certain routes that I really enjoy that are long-distance. It's still fun doing the whole deal, but just eliminating part of the very long cruise. It's definitely not a bad thing as you suggest, just that some of us can't actually do an entire long haul in real time.

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Remember:

Just because it is large, or has the capability to fly longer routes, doesn't mean that it always does.

Thank you for recognizing this fact!

 

Time acceleration is the worst thing anyone has ever added to the sim. If you can't fly it, don't fly it. That goes for weather, route length, route complexity, or aircraft type.

I must disagree. I don't regularly have time to do a 12 hour leg. I still enjoy planning the entire flight (fuel, w/b, wx etc). There are certain routes that I really enjoy that are long-distance. It's still fun doing the whole deal, but just eliminating part of the very long cruise. It's definitely not a bad thing as you suggest, just that some of us can't actually do an entire long haul in real time.

I do not think time manipulation is the worst thing anyone has ever added to the sim, but do not enjoy performing real-time long-haul flights, either.

 

I am in favor of maximum practical immersion/realism, so I almost never consider time manipulation during regular operations, but also recognize that we must occasionally utilize unrealistic simulator features and sacrifice immersion/realism in order to fit real-world commitments and time limitations better.

 

Basically, I only rarely use time acceleration/deceleration to satisfy real-world constraints, not to manipulate a flight and its characteristics so they maximize my enjoyment: I view FSX as a realistic simulator with potential, not a game for pure entertainment.

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Question for the pure simmers : when do you fly a 12-15 hours haul ?

 

I mean, I assume most of you have a job that occupies 8-10 hrs per day, then there is the time dedicated to sleep, then the time to eat, take care about other stuff / children / car insurance / showers / buy a newspaper / sex / watching movies / check the email etc...

 

So, when do you fly these long hauls ?

 

And, which is you strategy against FSX crashes ?

 

Thx

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Time acceleration is the worst thing anyone has ever added to the sim. If you can't fly it, don't fly it. That goes for weather, route length, route complexity, or aircraft type.

 

We all have our rights for our own opinion, however my opinion is the opposite, even though I avoid using time acceleration. I love to fly long routes, for example from EHFK,EHAM,EDDM, KJFK and PANC (thank you Aerosoft and FSDreamteam ) to KJFK, KSFO, KLAX, PANC, VHHH, WSSS, OMDB etc. I usually try to fly during weekends, departing early morning or late in the evening, use autopilot through the cruise (whole day or night) and do something else. Now that's not realism either to do something else during the cruise and miss important eicam messages in case of defect with the plane -> therefore I had to disable technical failures. Why to do this?

 

Well, I have a life also, other than FSX. I have a family which requires attention and I don’t want to listen my wife nagging me all the timeJ. Someone might suggest to change wife, maybe that would help, but then again, quess not…

 

Anyway, not accelerating, I avoid system crashes and autopilot errors etc and can still land at a time which is suitable for myself and for my family. Yes, its not realistic, but hey, as long as you are playing FSX, that is not realism either. I quess many of us have the same situation, so you have to compromise.

 

It is good to have options for different scenarios and that means we can decide what to choose and what suites us the best at that time. So what im trying to say ( I quess) is that you don’t have to use the acceleration if you don’t like to, but let other do so if they like to (no offense).

 

I cant wait the T7 to arrive so I can make a maiden flight from EFHK to KSFO with full pax and payload and with heavy lift off from icy runway in a low visibilityJ

 

Happy landings everyone!

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Just stating my opinion. As always, I never said you couldn't do it, or that they shouldn't have added the feature. In my opinion, however, it made the simulator into more of a game. It also ends up making an otherwise stable aircraft unstable, for the reasons I mentioned before. As your average simmer rarely ever knows where to place blame, it often (as in the case of this thread) gets pinned on the aircraft developer, instead of one's own system. Granted, the complexity and number of calculations the system has to run is dependent on how much data the developer throws into the simulation, but in the end, the stability of the sim is more dependent on your system's ability to process the data, and less on the aircraft developer's code wizardry.

 

I just run my flights as I run my real world flights.

I can't press B to set the altimeter in my Cessna, so I don't use it in the sim.

I can't accelerate my 5 hour flight down to DTS from BCB in a C207, so I don't use it in the sim.

 

Like I said earlier: if I don't have time to do the flight, I don't do it. I don't see the point. Why else would you be simming a long flight? If you wanted a flight in a short time frame, fly a shorter route. Large aircraft do IAD-ORD all the time. I've been in a 777 from IAD-MIA. Essentially what you're doing with time compression is treating everything like a regional flight. Takeoff, gear up, gear down, land. If that's what you want, the JS41 is excellent, and the flight legs on that are rarely ever longer than 1.5 hours.

 

In the end, I guess I just see it as trying to have your cake and eat it, too. Put more simply, I see it as cheating.

 

If that's what you need to do, then that's what you need to do, but I don't see you or your sim, so in the end it really doesn't matter to me what you do on your own.

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