I suspect you are comparing them to 100% manual braking, are you?
Comparing them to airbus and 787 autobrakes. Also when I select RTO for takeoff and 1 or 2 for landing I get the indicated orange light stating autobrake disarm
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If you’re getting the Autobrake Disarm light, that means you are pressing the manual brakes hard enough to disable the autobrakes. Either be more careful not to press the brakes while you’re landing, or add a deadzone so you can steer with the rudder during rollout without disarming the autobrakes.
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Yea the weird thing is it does it upon initial launch of the flight at the gate cold and dark. As you know we need to apply brakes to set the parking brake. Does that mean I’m applying to much brake at that time? I never apply brakes upon landing just rudder application but I guess it’s affected at the gate before the flight?
I have a somewhat unique problem with Ground Services. The KBJI airport has one jetway currently separated in the middle and no ATC tower or ground. Since their is no ATC ground there are no ground services unless it is a PMDG 737. When I request a jetway in the FMC, nothing happens. Passengers have to use the airstairs and the PMDG bus. However, when I request a pushback in the FMC the tug starts moving right away. I don’t know if there are any other uncontrolled airports with jetways.
Attached is a photo showing the KBJI airport and the 737-600.
You mean these?
It does have them. It’s just that it’s an expensive option so some airlines have them, and some don’t. But you can enable them in the EQUIPMENT OPTIONS. Look for “HGS”.
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Yes, in that case we would select on the MCP the next altitude restriction on our legs page. Then, 1nm before that point we would select on the MCP the next altitude restriction. And so on.
It could happen that they clear you to descend via star and then while you’re at it they give you a heading, so the altitude restriction disappears. In most cases the airplane will then show you that you’re low. When that happens we’d ask ATC if we have any altitude restrictions. They could ask us to be XXXXX or above abeam one of the original points of the star. If we didn’t do the direct with abeams, we’d use the FIX page to create an abeam point, paste it on the legs page and use it to respect the altitude restriction. This happens a lot in London and in German airports in general.
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For the RTO setting, applying the brakes before you start the take off roll would not deactivate the autobrake. I looks like you need to add a bit of deadzone. Are your IRSs aligned? Autobrake works fine in mine.
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I was looking for a British Airways livery for the 737-800, and couldn’t find one anywhere…until I stumbled across it in the livery manager under the name “Comair Limited”. See below. Anyone any idea why it’s called that and not BA?
It’s called Comair because Comair was a South African airline operator that had the franchise to operate British Airways flights in South Africa. They also operated the low cost airline Kalula. Unfortunately they went bankrupt a few months ago after a failed business rescue program that started in late 2019 if I recall correctly. I believe BA is looking for a new local partner. They had actually taken delivery of one of the new 737 Max jets that they ordered but had to send it back almost right away after entering business rescue.
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Thanks for that! I had no idea about any of that, so most informative.
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BA only ever operated 200’s, 300’s, 400’s and 500’s?
Then they switched to Airbus iirc?
I’m really tempted to buy this but I’m not keen on buying multiple (not cheap) packages in order to have a few variants.
I mean with JF, you get all of them when you buy their 146!
Great. This does confirm one of the techniques I use as well which is to “step down” the altitudes on the STAR vs. just dialing in the lowest point. it provides a nice visual picture of the path unfolding in real-time and you’re always aware where you are on that path. It requires more vigilance but can keep you out of trouble if, like you stated, ATC has a different plan in mind.
Yes I’m IRS aligned. I even get the anti skid inop indicator
I don’t want to step on any toes but it’s not strictly correct for all instances.
You would never get given a ‘descend via’ clearance in Europe because you would always be given a FL/altitude to descend to. Your clearance would be something like ‘you are cleared the CHASE2B, descend to altitude 6000ft, QNH 1015’. In that instance you would dial up 6000ft and are perfectly able to let VNAV do it’s thing complying with heights and speeds and slowing down at FL100. If at any point ATC took you off the lateral path of the STAR on a heading you can disregard speeds and altitude restrictions as they no longer apply, unless specifically told otherwise (and that happens often, ”be level FL140 abeam MCT” for example). You could, however, continue your descent to 6,000ft as you’ve been explicitly cleared to it.
On the other side of that coin, and using the USA as an example, you are very likely to be given an actual ‘descend via’ clearance. ATC would say something like “Cleared to MLBEC, descend via the BDEGA3 arrival, San Francisco altimeter 29.97”. In this instance you set the lowest altitude per the arrival plate (on the BDEGA3 for KSFO this is 11,000ft) and our SOP is that you must be in VNAV to do this, setting QNH at an appropriate time without prompt from ATC. However, the crucial difference is if, as above, ATC took you off the STAR and on to a heading (and therefore out of VNAV) you would need to dial in the next available altitude restriction and expect to level there until put back on the STAR and cleared once again to ‘descend via’. In reality you would check with ATC and they would then give you a radar descent. Equally often that’s not the case which is where you start having to manage energy.
Hope that makes sense.
@FrontSideBus08 You’re correct. BA never flew the NG themselves but Comair did until very recently.
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I’m a big fan of JF and the 146 is awesome but I don’t think this comparison is fair. The difference between the 146 variants is marginal compared to the 737 variants. Plus except -600 (which costs only 35 USD - a price of a dinner for two) you also get cargo and business jet versions. And I also guess that the development of the 737 is a bit more complicated as it has VNAV and more systems to model. And why not to get just one variant you like the most? There are tons of liveries available for each variant. This theme goes over and over and I will probably never get this “I must have all the variants but don’t want to pay that much”.
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So you basically re-wrote exactly what @FormerSnail5736 and I posted. Correct, there are methods to account for a strict descent profile like you’d see in Europe, as you stated, or to handle a “descend via” like you can get here in the U.S.
Did I? I’ve re-read the posts and I don’t think I did.
You asked what the SOP for a ‘descend via’ instruction might be. You don’t get descend via clearances in Europe and unless I’ve missed something what @FormerSnail5736 described is not the procedure for that instruction.
In Europe if you’re on an arrival and get cleared to a level you are expected to comply with the altitude restrictions unless either taken off the STAR or you get told to disregard them. That is completely different to an actual ‘descend via’ instruction like you would get in the US. The crucial difference is in Europe you would only ever descend to a cleared level. In the USA (other countries do this as well) the descend via instruction is giving you implicit permission to descend via the approach plate, a very different thing altogether. People can and do get it wrong by mis-interpreting the approach plate leading to a level bust.
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It’s all good. Just more info. Yes, @FormerSnail5736 answered this question with these options for a typical European descent and one that might be more typical in the U.S. The OP wanted to know what you do at TOD with the MCP altitude. Dial it all the way down to lowest level, or some intermediate altitude based on the arrival.
Hello,
I am rather new to 737-8 and I am practising RNP approaches with IAN functionality (LNAV/VNAV too) and I have noticed that at some airports glidepath angle in the FMC is different than the one presented on the approach charts. As an example I have tried to use IAN on EPGD RNP 11 where the GP is 3.5 angle and FMC has shown me 3.39 GP angle - that resulted I was too high on the path. On the other hand on another airport EPKK I had exact GP angle in FMC legs as on the chart which resulted I was on the profile until minimums. I tend to be too high all the time at minimums during these approaches.
Is it possible to change gp angle in the FMC or is it the way it is. What is the reason that GP angle differ in FMC and is not exact as shown on the charts for specific airports?
As an Airbus frequent flyer having hard times to get this logics will appreciate your assistance and explanations