martinboehme

I also did not realize this. I did see some mention that at least 2x was supposed to be possible - maybe through the MCDU or EFB? Haven't been able to find that option though. The time I can devote to simming is limited, so this really makes anything over a one hour sector not very feasible for me.

Can someone tell me how to increase the sim rate? The usual MSFS sim rate commands don't seem to work. On Discord, someone said there's a sim rate option in the MCDU, but I wasn't able to find it. Apologies if this has been asked before - I did a search but that didn't turn anything up.

No United either, as far as I can tell?

Same here. Download seems to be pretty quick.

In one hour, actually.

While they're at it, could they fix the typo on the price too? 😉

I'm not sure they said the bug was found by a streamer. And even if it was... a bug is a bug, no matter who finds it, and if it's serious enough, you need to fix it before release. It'd be preferable to find the bug earlier in the process, but that's how it goes. Edit: And, as others have pointed out, some of the streamers are testers too, or, in the case of @KatiePilot, even developers.

That's good news! This must be relatively new? I know for a long time they were limited to 2x, but said they were hoping to overcome that limitation.

Thanks for the confirmation (even if it's not what I'd hoped)!

I would be interested in this as well. It may sound funny, but one of the features I was hoping for from the Fenix compared to the FBW was being able to do more than 2x sim rate. I have limited time for simming, and time acceleration enables me to do some of the longer sectors.

As we await the release, I wanted to recommend a resource that I think will be useful to those for whom the Fenix will be their first Airbus -- and maybe also to some who have been flying Airbuses for a while. I'm talking about Mike Ray's A320 Pilot Handbook: Physical version: https://www.utem.com/shop/index.php?l=product_detail&p=104 Downloadable PDF: https://www.utem.com/shop/index.php?l=product_detail&p=18 Admittedly, this book isn't cheap (certainly the physical version isn't), but it was invaluable to me when I transitioned from the familiar Boeings to the alien Airbus. There's a lot of solid technical content here, and though the presentation may at first seem a bit whimsical, I actually found that this helped me absorb the material better than a dry description would have. What I find particularly valuable is how the book points out various "gotchas" ("why has it gone into TOGA LK again, and how do I get out of it?"). Just an honest recommendation; I'm not affiliated with the author in any way.

🙏 Then I hope you're suitably entertained by my amateurish fumblings here! 😉 (Intentionally speaking only for myself.) On a more serious note, I'm very much aware that I'm taking time out from pretending to be an airline pilot so I can pretend to be a performance engineer. My goal with both of these is to challenge myself and learn -- and thanks to the input from people such as yourself and @Stearmandriver I'm doing just that!

Nice find! I see you've chosen the midspan airfoil, rather than root or tip -- I assume you're hoping this will give a good approximation of the behavior of the wing as a whole? This is the drag at the speed achieved at the end of the runway. I assume you're simply conservatively applying this drag from the start of the takeoff run? It looks as if this is just the drag produced by the wing though -- not the rest of the airframe? Absolutely -- my hope was that I would end up learning something, which I did (see below). And to be clear, I'm certainly treating this as an academic exercise. For one thing, the idea of trying to lift off at exactly the stall speed and remaining in control is pretty impractical. Thank you -- I did not know that! For those following along, I found an explanation with some more details here: https://aviation.stackexchange.com/questions/90123/what-is-a-ram-recovery-point By the way, going back and looking again at the numbers I used, I noticed that the 89 kN correspond to 20,000 lbf thrust. It looks as if the -700 typically uses the 24k engines, so that could at least partially compensate for the various effects I've neglected. Yes, I was just handwavingly assuming that it would be possible to achieve CLmax on the ground. Tailstrike pitch attitude on the 737-700 is 14.7 degrees. From the data that mrueedi quoted, the critical angle of attack appears to be about 15 degrees. I don't know what the angle of incidence is; I'm guessing it's small but positive, so it seems pretty clear we won't quite be able to achieve CLmax. A good point -- though those 150 knots are likely a significant margin above stall speed and below tailstrike attitude. They wouldn't investigate flaps up takeoff performance per se, but I do think they would make sure that, among other things, the aircraft produces a) the correct amount of thrust during the takeoff roll, and b) the correct amount of lift at various angles of attack with flaps up. If they've done those things, I think you should see reasonable behavior for a flaps-up takeoff? If those 5200 ft are a takeoff distance (which published numbers would typically be), then they assume an engine failure at V1 (or, more precisely, slightly before V1) and achieving a height of 35 feet at the end of the takeoff distance. The OP's scenario, on the other hand, is assuming both engines operating and lifting off potentially right at the end of the runway. The question is whether that leaves enough "wiggle room" to do the takeoff with flaps up and above MTOW. As noted, it is of course a purely academic question.

Instead of turning this into a slagfest, could people just keep this to what's being shown in the streams, for the benefit of those of us who can't watch?

Another tidbit that stood out to me is the approach they're taking to the pre-departure process. If I understand correctly, the doors are automatically closed and the jetway removed once boarding is complete. To me, having to do this myself on other aircraft has always felt like a chore. For those who enjoy it, I assume there will be an option to do this yourself (and more power to you!), but to me, the fact that there will be other crew members doing their bit as you're working in the cockpit is something I imagine will add to the immersion.

Look at the insane amount of detailing on that Lufthansa vertical stabilizer shot. I'm not usually someone who places a lot of value on the external model - it's more about the cockpit for me - but my word, that looks good. Maybe I'll turn into a rivet counter too...

Oops... thanks for catching that! I originally found the value of 1.48 here: https://forum.flightgear.org/viewtopic.php?f=4&t=20647&start=30#p198182 But that value applies to the Classic, and besides, the value is reconstructed from stall speeds taken from an FCTM. I then decided to be more conservative and use the optimistic best-case value of 1.8 for jet transports but forgot to update the calculation... Good find! However, if I'm reading the diagram correctly, CLmax looks more like 1.15 to me (at an AoA of 11 degrees)? That would reduce the lift quite a bit. The source doesn't say which variant of the 737 this is for though. I believe the NGs have a different wing than the Classics and Jurassics, so it's not clear whether this applies to the -700. Agree - I'm pretty sure drag is not negligible, which makes the calculation "optimistic". I wasn't able to find good numbers for the parasitic drag on a 737 though. Thanks to you too for checking my numbers. This is getting embarrassing... I should have checked my calculations better. With the correct numbers, the results become: a = F / m = 188 kN / 77564 kg = 2.42 m/s v = a sqrt(2s / a) = 2.42 m/s * sqrt(2 * 1508 m / 2.42 m/s) = 85. 4m/s L = CL rho v^2 / 2 A = 1.8 * 1.225 kg/m^3 * (85.4 m/s)^2 / 2 * 124.58 m^2 = 1001.7 kN That's a fair bit more than the weight of 761.8 kN, so the picture is starting to look quite favorable. The source that @mrueedi quoted suggests though that the assumed CLmax of 1.8 may be very optimistic. With the CLmax of 1.15 from that source, we get a lift of only 640 kN. That would not be enough, and that's without taking drag into account. So in the end the picture seems inconclusive. The main point that the answer hinges on is getting an accurate value for the CLmax of the 737 NG wing.

An interesting discussion. Some have stated that it’s impossible to answer the question whether this takeoff would be possible in reality, but I believe that at least Boeing should be able to answer this question based on their flight test data, and I think we can even get some of the way using only publicly available information. There are two questions we need to answer: 1. What speed will the aircraft reach by the end of the runway? 2. At that speed, how much lift will the aircraft produce in the maximum attitude that can be achieved on the ground (i.e. tail strike attitude), in a clean configuration? If the lift is greater than the weight of the aircraft, the takeoff should be possible (assuming no obstacles, perfect execution etc.), though of course not necessarily legal. Boeing’s test data should be able to answer these questions. Regarding question 1, they will have performed extensive takeoff acceleration tests. While they will likely not have performed these beyond MTOW, the data for these tests should extrapolate reliably beyond MTOW: Aerodynamic drag is not affected by the TOW, and there’s a simple inverse relationship between mass and acceleration. Tyre rolling friction will increase with TOW, but it’s a simple physical principle that should extrapolate reliably, and its influence is likely small anyhow. Regarding question 2, the answer to that does not depend on TOW, and Boeing will certainly have precise lift polars for every configuration. We’re not Boeing, but let’s see how far we can get with publicly available data. First, let’s set some parameters. I’m going to assume a sea level ISA day with no wind. I don’t know the TOW that the OP used, so I’m going to assume MTOW. From http://www.b737.org.uk/techspecsdetailed.htm, we find the following relevant data for the 737-700: Static thrust 89.0 kN per engine, so 188.0 kN total MTOW 77564 kg Wing area 124.58 m^2 (Static thrust data is often quoted for sea level ISA conditions, so I’m assuming that’s the case here.) The runway length at EGLC is 1508 m. Let’s answer question 1 first. In doing so, we’ll have to make some simplifying approximations: We will neglect drag and tyre friction We will neglect the increase in thrust due to the ram effect, i.e. we will assume that thrust remains constant at the static thrust These two approximations have opposite effects, but all in all, I expect that we will be overestimating the speed. Acceleration tends to reduce during the takeoff roll, which implies that drag and tyre friction have a larger effect than the ram effect. What this means is that the calculation will be too optimistic: It may predict that a takeoff is possible when in reality it is not. Conversely however, if the calculation says the takeoff is not possible, we can be pretty sure that it would not be possible in reality. With that, let’s plug in some numbers and see what we get. Acceleration is a = F / m = 178 kN / 77564 kg = 2.3 m/s This gives us the following speed at the end of the runway: v = a sqrt(2s / a) = 2.3 m/s * sqrt(2 * 1508 m / 2.3 m/s) = 83.3 m/s That’s 162 knots, which seems like it might be barely enough. Let’s continue with question 2. I’m going to assume that the 737-700 can reach clean CLmax in the tailstrike attitude. Unfortunately, it’s hard to find a clean CLmax for the 737-700, so I’m going to use the typical CLmax ranges found in this source; again, to be optimistic, I’ll use the top end of the range, giving me a CLmax of 1.8. With an air density in sea level ISA conditions of rho = 1.225 kg/m^3, the lift we can achieve becomes L = CL rho v^2 / 2 A = 1.48 * 1.225 kg/m^3 * (83.3 m/s)^2 / 2 * 124.58 m^2 = 783.6 kN The weight of the airplane at MTOW is Fg = m g = 9.81 m/s^2 * 77654 kg = 761.8 kN So we’re achieving just slightly more lift than the aircraft’s weight, but keep in mind that we’ve made various optimistic assumptions and approximations. Without these, it’s possible we wouldn’t quite be able to achieve the required lift. We could, however, make the conditions more favorable than sea level ISA, nil wind. Lift increases with the square of the airspeed, so a ten-knot headwind, say, is going to help a lot. We could also lower the temperature, which would give us both more thrust and more lift. Changing both of these environmental conditions could be enough to compensate for the optimistic assumptions we’ve made. (@Bad_T, I'd be interested to know what the weather conditions were for your test.) In the end, the results are close enough that we can't really make a definitive statement either way, but I'd say we can conclude that getting a 737-700 out of EGLC at MTOW is at least not wildly unrealistic.

Have you heard of https://en.m.wikipedia.org/wiki/SAP?

It's complicated and depends on the aircraft type. If you're talking about multiple Grumman G-21s, for example, you would call them a gaggle of Geese. A group of DHC-1s, on the other hand, is a scurry of Chipmunks. Several A-10s would be called a passel of Warthogs. And, of course, if you saw a formation of B-17s passing overhead, that's simply an Aluminum Overcast.

In the UK, try EGLC London City - definitely popular with the biz jet crowd.

One way you can tell directly that it's not an airport is that it's missing the altimeter setting.

This is implied by the title of the post quoted in the OP: "Are cloud bases in new METAR system in AGL or MSL?"

To clarify: The specific issue here that Asobo has acknowledged is that cloud heights in METARs are wrongly being interpreted as MSL instead of AGL. At higher-elevation airports, this has the effect of showing the clouds at a lower altitude than they should be.

It knows your heading and your track as well as TAS and GS. From that, it can compute wind direction and velocity -- this is essentially the inverse of the computation you would do when flight planning to compute your wind correction angle from the desired track and the wind.