Speaking as a non-pilot I can certainly say that I appreciate having the RL pilots engaged and able to answer questions and provide RW perspectives, particularly for the more complex aircraft.
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I’m not entirely sure about that. Your photo shows the airplane in the cruise and the flaps are up.
The behavior of SPD INTV is different between Basic VNAV and Common VNAV too. But I think the key here is the flaps.
I haven’t flown in 15 days (annual leave). I’ll check next time if the AT mode changes to MCP SPD when the flaps are not up.
It doesn’t, for the reason I stated: if you’re in VNAV, the FMC is controlling speed. I think you’re talking about the difference between the vertical modes VNAV SPD and VNAV PATH; we’re talking about the autothrottle mode.
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I am talking about the autothrottle mode.
If you’re “on approach” with flaps not up and use SPD INTV (during an NPA), the airplane will stay in VNAV PTH but it’ll use FMC SPD. The vertical path will be geometrical (PTH) but the speed will be controlled by the FMC. It does this knowing that the increased drag provided by the flaps will help achieve the speeds without making the descent path more shallow. This is what allows us to fly non precision approaches in VNAV all the way to the runway while still flying standard speeds.
But like I said I’m not entirely sure as I haven’t flown in weeks and I haven’t done an NPA. It could be that it stays in FMC SPD but the speed window opens to follow what you say (MCP->FMC->A/T)
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Related question: when do you turn off A/T on your approach? I’ve been practicing some Go Arounds, and in watching a couple of Youtubes that have A/T still on when calling GA and hitting the TOGA button.
I feel like we’re saying the same thing here? “On approach” logic doesn’t change this behavior, so with flaps up or down, the autothrottle mode will always remain in FMC Speed with speed intervention selected.
Most operators turn the autothrottles off when disconnecting the autopilot. There are a few that land with autothrottles engaged, despite the fact that Boeing does not recommend this. You’re going to do whatever your company trains you to do.
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FWIW, I d/c a/p at 2,500’ once approach is stabilized and d/c auto throttle shortly after when confident hand flying. On long final when conditions are favorable for single pilot ops, all this may happen sooner.
It’s an interesting question. Like anything involving a large group of people I guess, there’s going to be variability.
It’s definitely true that a percentage of airline folks see flying as just a job. They have zero interest in flying outside of their airline job, even if they have the opportunity to do some fun GA type flying. To them, flying is nothing but a paycheck. The idea of pretending to be at work on your days off, for free, would be absolutely ludicrous to these folks.
Then, there are people who would find the sim cool for other types of flying like GA, or DCS for tactical jet stuff, that they don’t get to do anymore. It could be seen as nostalgic, or a way to get a bit of a glimpse into a style of flying they’ll never do. But airline simming? That’s pretending to be at work on your days off… Who would do that? 
Then there’s folks like me: inveterate aviation geeks; I have to own it haha. To me, using the simulated version of the work airplane isn’t about pretending to be at work; I’ve decided it’s about evenly split between marveling at what the technology can achieve at home in a desktop sim, and marveling at the human factors aspects of it. The instructor geek in me finds it absolutely fascinating that in, say, a simulated line flight on Vatsim, I see the same threats pop up regarding automation management, workload management, non-standard comms w ATC etc, that happen in reality. It’s a great look at the human factors and how similar they are because the key ingredient isn’t the real vs simulated airplane… But the human.
So, variety. I will say this: most of the older generation of actual airline pilots would regard this as a very weird hobby. They would see this as a weird sort of role playing video game and would find it kind of childish for an actual pilot to be doing. This is why I use a pseudonym on everything sim-related that requires use of a real name. I know there are forums that threaten banning for this, but I’ve always been involved in training departments at previous jobs and would like to be again at my present airline in a couple years when the kids are out of the house… The last thing I’m going to risk is someone googling my name and finding a bunch of posts on flying video game forums. If a forum wants to ban me for that… I’ll survive lol.
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Hi guys, maybe a silly question but do some of you use Tankering when doing return trips? With a pilots life I’m with Alaska right now and when doing return trips from Anchorage to let’s say Nome or Kodiak Island i would think they would not refuel at these more remote locations. To simulate this i was wondering how to input this in Simbrief. One options would be to add both block fuel values. But that seems excessive. Other option i thought of was adding the trip + taxi from the return trip.
Grtz M
Like Stearmandriver2, and what the FCTM says, the autothrottle shouldn’t be used in manual flight. The 737 does not trim out the thrust changes automatically like newer Boeing airplanes (777 and 787) so if the autothrottle adds thrust to overcome a gust without the pilot noticing, they will need to counterintuitively trim nose down. That’s why Boeing doesn’t recommend it. Most airlines follow this and disconnect the autothrottle whenever they fly manually (except for take off and climbs).
Then, and I believe this is a purely European regulation, the autopilot in single channel mode has a minimum use height (MUH 158ft AGL for the 737). Below that height the autopilot cannot be used unless it’s being used in dual channel (autoland).
So basically if I disconnect the autopilot at 1000ft or at any point above 158ft AGL for landing I will always disconnect the A/T at the same time. The go around will be manual and the thrust levers will not move when I push TOGA. You can reengage automatics during the go around as soon as you’re above 158ft if simulating European operations with a MUH).
When we actually disconnect it is completely up to us. If it’s a nice day with not a lot of traffic and the airspace is not busy we may disconnect it even 15 minutes before landing (if the airspace allows it and the colleague can take the increased workload). If it’s busy or it’s unreasonable to disconnect we’ll keep it on until cleared to land with the airplane fully configd for landing.
If the approach is being conducted dual channel for an autoland both the autopilots and the autothrottle will stay on until touchdown. The go around will be automatic and the thrust levers will advance automatically when pushing TOGA.
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Yes, tankering is common. I’d say I do tankering round trips twice per month but of course this depends on the airline and the operation.
You wouldn’t add both BLOCKs because block contains fuel that you will not necessarily use (Alternate, final, Cont). I don’t use simbrief so I don’t know if it has this feature. When you’re loading the FMC add as much fuel required so that the fuel on arrival is equal or greater than the block required for the return trip. You can check this is PROGRESS 1/4 page.
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There is a Tankering setting in SimBrief under Fuel Planning - custom fuel policies. While I haven’t used it, I have used the other options like Extra fuel and it has worked just fine.
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Fuel is commonly tankered in both the Arctic and Southeast Alaska systems, but all stations absolutely have the ability to fuel and you’ll often take at least some fuel at these locations. The exception used to be Red Dog, but I don’t think that’s been true for a long time now. I mean Red Dog was gravel once upon a time too, which meant only the -200s with gravel kits could go in there ;).
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Thanks for the input! That last point made sense and i will use that as a rule of thumb. With both return briefings from simbrief i can easily calculate this.
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Yes i noticed and will use the tankering field. You do have to calculate the amount yourself though. Which is fine.
Great info! Thanks! There is a great freeware version of Barrow in MSFS. It’s one of my favorite locations. Really gives the end of the world vibe.
I suppose another way to go about it would be to choose an alternate that is as far away from the destination as you would like to have fuel tankered for. This might not be realistic operations, but it may be a way to force SimBrief to do the calculations? Just thinking out loud from the POV of casual simmer than any airline’s ops. If one actually needs to fly to a nearby alternate, then that much less fuel is tankered, of course.
Sounds like Barrow lol. I’ll check that out, I haven’t seen it. There’s a really great Kodiak freeware on .to if you don’t have it already.
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That is actually commonly how it’s done. Arctic system flights are typically planned with an alternate of ANC or FAI if possible, and Southeast flights are planned with an alternate of SEA or ANC. This isn’t always possible if payload is maxed out with freight, but it often is, and provides a lot of fuel which means a lot of options if you do have to divert (you don’t actually have to divert to your paper alternate, that’s just for dispatch.). All the times you DON’T divert mean you have a bunch of through fuel when you land and often don’t need any more.
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