I don’t think that 737 takes the local pressure into consideration when calculating Vref. There’s QNH input in the descent forecast page but I guess that’s only for VNAV fine tuning.
Vref is an INDICATED AIRSPEED (calibrated if you will). Wings “feel” indicated airspeed not true airspeed. If the density is low you’ll just need a higher TAS to achieve the required IAS. So no, Vref is not affected by local pressure or density. It’s only affected by the mass of the airplane at a given configuration.
Landing at sea level in an ISA day if your Vref is 140KIAS your TAS will also be 140KTAS.
Landing at 10000ft elevation on a 30ºC day if your Vref is 140KIAS your TAS will be 173KTAS.
This is important because the hotter and the higher it is (lower density) the greater the GS will be for a given Vref. So brake cooling becomes an important consideration. That’s why in summer season it’s more common to use reversers and F40 even on dry runways. Vref will be the same but the airplane will be travelling faster relative to the ground and will carry higher energy.
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I misread - you are right. Only landing distance is affected.
@DrVenkman3876, as @FormerSnail5736 says above, speed won’t be affected, but landing distance will.
Here’s an example using OPT.
I threw in a bunch of random data at a random airfield on a 737-700.
Vref30+5 with this random data is 140KIAS and a landing distance of 6210 ft.
If I ONLY change the pressure and not the temperature (29.80 to 30.00in) from the original values:
Vref30+5 is now 140KIAS and landing distance of 6171 ft.
Makes sense… with more dense air, the TAS will be slightly slower with a few feet better stopping distance.
Now, I change temperate and pressure (raise the temperate from 0 to 20C and pressure from 29.80 to 30.00).
Vref30+5 is now 140KIAS with a landing distance of 6594 ft.
Makes sense, a higher temperature will reduce the density of the air and increase the TAS. The stopping distance will be longer.
Vref is only influenced by aircraft weight, flap setting, and indirectly by Vref additions due to wind and gusts.
Everything else only affects landing distance.
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Exactly.
Also note that using reversers would not reduce the braking distance because the runway is dry. It would only reduce brake heat. Reversers only reduce landing distance on non-dry runways.
“CAUTION” there means that the brake fuses may melt. Even if they don’t there needs to be an engineering inspection one hour after landing before taking off again.
65000Kg is close to the maximum landing weight of the 737-800.
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Hello, I am wondering if it’s possible to change the colors for the displays but have it only apply to the specific livery and not the whole plane? I was able to change the colors in P3D, however it would apply to every livery for a specific varient/model.
Thanks
Question - Isolation Valve settings - just throw it in Auto and forget about it? Move it to Open for the startup or something else?
-On the ground before engine start it’s OPEN.
-During engine start it needs to be OPEN (With packs off).
-After both Engine Start it’s put in AUTO and it stays there.
-After Engine Shut Down it’s OPEN again (and you can start reading from the top).
Apart from that there’s a bunch of QRH checklists and supplementary procedures that have you opening or closing the valve (No Engine Bleeds Takeoff, Isolated Pack Operation, No Engine Bleed Landing, etc…)
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If the switch is in Auto, the isolation valve will be open with any pack or bleed switch Off. Our procedures have us start with the switch in Auto.
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Yeah that works too.
I believe the reason for our procedure is that the isolation valve is AC powered. So we always open it after shut down just in case someone needs to do a battery start with no AC available to open it.
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One for stearman and former snail…
I’m turning 37 next month…
Is that too old to become a real pmdg 737 pilot or is there still a little slither of time left…
I’m pretty sure you can be a PMDG 737 pilot at 105 and no one will mind, though some might be impressed. 
If you’re asking if 37 is too old to pursue a real world airline pilot career, that might depend somewhat on where you are in the world, but in general the answer should be no, not even close to too old. In the US, I can tell you it’s no problem at all.
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Provided you have the money to start and complete pilot training, yes, it can be done.
In Europe the initial licenses up to CPL+IR(ME)+MCC+FrozenATPL should not take longer than 2 years, 3 max. With that you can already get a jet job in Europe as a cadet but you may need to pay for the type rating (and avoid being bonded). The main factors are the money and your spare time.
One thing is important: Don’t confuse what you perceive about aviation through Youtube videos and MSFS with the actual life as an airline pilot.
Life as a pilot varies wildly depending on where you are, who you fly for and the operation you end up doing. A short haul low-cost job flying a Dash 8 is not the same as life flying a 777 long haul at a major airline. You may have to do a bit of the former to reach the latter. The excitement of flying the airplane wears off quickly and then you’ll be left with a job like any other. It can be a great job don’t get me wrong (I love it) but you can’t sustain it on what you imagined about it through MSFS alone.
If you’re still sure this is what you want and that it’ll make you happy then nothing will stop you. Nothing stopped me… I was obsessed with Flight Simulator since FS5 back in the 90s. I started flying IRL back in 2002. Then I did all sorts of unrelated things and didn’t seek an airline job until the early 2010s well into my 30s. I was lucky to go straight to a jet. So now I’m turning 42 and just now I feel like I’m finally about to start the career I wanted to have (Moving on to long haul in April). So if you think about it you are only 5 or 6 years behind where I was after all those years away from flying. If you get your licenses now, if you’re in Europe you could be flying 737/A320 as a cadet when you’re 40. Add 3 or 4 years to that and you’ll have enough hours to move to a better airline or stay where you are and focus on reaching command. At that point it won’t matter when you started. So get a PPL and go from there.
So are you too old? Not at all. Won’t be as easy as for someone completing initial training in their 20s but it’s not impossible at all. Airlines are desperate for captains now. Good luck!
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Having delved into the low & slow / VOR and NDB world for a while it’s been months since I’ve flown any heavy iron including the 737. Won’t make that mistake again. This aging brain forgot everything about how to fly this fine bird and what a rewarding experience it was. So I started from scratch relearning everything today and in no time I was up again.
I was several versions old by now and I realized that many updates transpired including the tablet. So I researched this informative thread and came to the conclusion I’d probably need to uninstall and do a fresh install to avoid several problems that have been experienced according to the forums. Laziness got the better of me however and I just updated using the Ops Center. One click, that was it. I was shocked that everything thus far seems perfect. All previous settings there, all add on liveries, all systems working great! The update did trash my custom cabin view settings but that took all of 2 min’s to re-do.
The most pleasant surprise for me was that all the changes did nothing to impact the outstanding sim performance I’ve always enjoyed from this product. For me that’s the most important thing for an add-on aircraft and I dare say PMDG remains the king of the complexity/performance ratio for MSFS. Now I haven’t yet fiddled with the tablet and may never do so, the present experience being immensely satisfying for me already. Thanks to PMDG for creating such a magnificent offering for our sim.
I began commercial flying at 36 years old and ended up with 15 years as a 747 captain. Luck and persistence play big roles in any airline career. So enjoying the 737 NG, flew all the 737’s before this series IRL, so it’s fun learning some newer technology. Looking forward to the 747 as that plane was always my true love as a flying machine.
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I just want to say a massive thank you to former snail and stearman and also captain Tom…
To you stearman… Gave me a massive laugh 
at 105 I can still fly planes
Former snail…
I guess it’s definitely the case of a passionate aviation geeek from the 90s when I first ever saw a Bae 146 depart from my old home town in NZ and growing up on Hs748, 737-200s at Rotorua, going to Auckland airport and seeing the last of the 727s, Dc10s, 742s… that then became ATR, A320s 777s of today
I always had a massive passion for aviation…
Being from NZ and knowing just how small the pool is, mixed in with not having the best time during my teens with a few hard times (you know… The usual teen mental health stuff…) as a result, not so great high-school marks… I kinda just thought it was a forgone conclusion…
But…
With a uk passport that I got through my dad, living here for theast two years and seeing jist how many aircraft there are and of course msfs2020…
Giving me a whole new outlook on flying… I’ve been a simmer since “for windows 95” it’s only been the last four years that I’ve learnt how to program the fms, do VOR approaches and after doing RL truck driving and knowing the real side of what aviation pilots would have in similar terms…
I just have that thought of maybe… Just maybe there is a small window still there…
What would one tip be from you to decide if I would actually be able to pass one of those full courses… Would I have to go to night school and be better with math…??A medical first…??Eye test… ??
If I can do almost everything in a pmdg 737… Am I almost there 
(msfs and real world is completely different I bet…)
What would be one thing you see fellow pupils fail on the most (apart from a medical or eye exam)
I guess what I’m asking, regarding today and becoming a airline pilot…
Is it like those golden ages of flying…1910s-1930s… You just have a natural skill and passion of operating a plane and it’s all about (hands on practical/experience) where you just flew a plane and it went from there “winging it.”
More of the 1950s-1980s you had to know everything that there need to to be regarding complex math and trigonometry skills off the bat and navigation…
Or is it a lot more automated and a bit of both…
People that you studied with…
Were there the golden ages type that had that passion but not quite the math and navigation skill that wasn’t a issue, just the natural ability to fly that got them through …
Or was it those people who just didn’t quite make it…
And was it pure math and physics type students that were the only ones standing so to speak…
I’m guessing there are some pilots who only did it through parents and were naturally gifted with math and physics that don’t really want to be pilots but are…
Some who struggled with the math and physics but somehow managed to just scrap through that have gone leaps and bounds
And some who just simply had the 100% passion ans drive but the math was just the only thing stopping them from reaching their dream…
If there was one thing apart from a medical that would stop someone passionate, dead in their tracts, especially when it came to the very last exam or hurdle… What was it that saw your mates in class not join you to the finish line
I would take advantage of that UK passport, head to Europe and find the cheapest place you can get your licenses. The airlines don’t care where you got your licenses from, especially the ones who would hire you as a cadet and train you from scratch. In Ryanair I flew with people who got their licenses for 70000€ working two jobs and people who spent 140000€ in a posh flightschool paid by daddy. It makes absolutely no difference at all. So Poland and other NE European countries are a good option to obtain your frozen ATPL. Spain too (long good weather seasons so less flight cancelling). The theoretical exams and the syllabus are the same and completely unified in every European country. Then I’d just try to join any serious airline that takes cadets: Ryanair, Wizzair, Easyjet, etc. They won’t give you the career of your dreams but the training will be high quality with a very quick progression towards command (4 or 5 years). After a few years in one of these companies it won’t be difficult to get a job at any airline in the world including US or Middle East carriers.
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There’s all types of people who are pilots… and that’s a good thing. It provides different perspectives, different skills, and different strengths.
I’ve known people who had zero idea what they wanted to do with their life during High School, but were well accomplished in school and extracurricular activities/sports. On a whim, they decided to apply to the USAF Academy (which some kids spend their lives up to that point trying to get a slot and don’t get the chance). Once in, they had no idea what they wanted to do and on a whim, decided to go for a pilot slot and had no idea what it was about. They graduated, went to pilot training and finished at the top of the class. They ended up flying F-22s.
I’ve seen other people who were airplane fanatics since they were a kid who either dropped out of pilot training or were eliminated. Sometimes, their expectations of what they thought flying was about didn’t match reality. Sometimes airsickness got the better of them. A few people find out they have a fear related to some aspect of flying they can’t overcome. Sometimes they didn’t pick up flying skills fast enough. Some people couldn’t figure out how to think ahead of the jet and would only react to things after they happened in flight. Much of the time, they just didn’t like flying as much as they thought they would.
For the people who become fully qualified pilots, there are people who see it as “just a job” and have zero interest in aviation besides getting a paycheck. For many of them, they said they never spent a single cent on aviation and they refuse to ever spend a single cent to fly on their own. There are others who spend every waking moment in aviation and their life is centered around it. Then there’s everyone else in between.
There are some “Johny Goldenhands” types that have really good stick and rudder skills and pick it up immediately. There are others who don’t have as good stick and rudder skills, but have really good conceptual understanding of aviation and have a phenomenal memory for the tens of thousands of pages of rules, regulations, and flight manuals. There are some people that really struggle initially, then something finally clicks with them and they get really good at it. Then there’s everyone else in the “average” category.
Tying this back into PMDG 737, these days, flying large aircraft is mostly focused on systems monitoring: data input, confirmation of data input, monitoring correct progression of the planned flight profile, understand how to get the systems to respond correctly when you need to deviate from the plan due to weather, ATC direction, or aircraft malfunctions, and having the knowledge and training to work though unexpected events, malfunctions, or anything else you can’t 100% plan and program in advance.
Modern complex aircraft have systems and avionics handle most of the math, physics, and navigation problems for the aircrew. That’s how large aircraft only need 2 people in the cockpit now. Like the PMDG 737 demonstrates, modern complex aircraft are flown through following established procedures, correctly using complex systems and avionics, and thinking ahead to start working through changes to the plan early. Pure stick and rudder skills are now relegated to a secondary importance until an emergency situation takes place.
Most pilot math these days is simple rules to follow to quickly calculate fuel usage, how far it will take you to descend, and some navigation related rules of thumb. If you can add and subtract, you have the math skills you need to fly in modern aviation.
To put it more clearly, many US airlines have removed the requirement to even have a college degree. You just needed to have graduated high school now…
Medical conditions, self-doubt, lack of desire, or money, really are what will keep the vast majority of people out of aviation these days.
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Nice summary. I do wonder about the main focus of pilotage these days is being a competent “systems manager” at the expense of basic flying skills. Who knows, maybe that’s for the best. Saw another RL pilot above mention that on occasion, in his airline, they will fly approaches based on raw data. The thought of that filled me with terror. From a simming perspective, I consider myself to be a fantastic “systems manager” and always get the PMDG 737 from point A to point B with no drama. Flying just with the numbers, is way outside of my comfort zone.