4deg AoA is way too high!
739NG too heavy?
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Why on earth do you select CRZ limit while still climbing and especially at such low altitudes?
You should always climb with the CLB limit selected.
I don't know what the simulated weight of the Aerofly 737 is, but e.g. the A320 IRL struggles with anything above FL300 at high weight.
Check the pitch attitude during cruise. If it's higher than 2-2.5deg you are simply too heavy for this FL.
My airplane art:
1) it was the only way to get it into CRZ without stalling out
2) even at 35,000 it was doing about 2.8 degrees nose up, hence the point of this entire thread where i suspected the simulated weight might be too high for any altitude higher than flight level 350
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I believe someone already mentioned this.
Fuel weight guys. Also configure the FMC including the proper weight, and CRZ altitude etc so it should adjust what CLB and CRZ N1 is.
I use to do crazy tests in many airplanes and this is one of the few I've been able to take off, get done altitude, turn around and land back with only 1 engine from standing still position at lenghty runways.
So no weakness imho, but perhaps... missconfiguration?
About flight levels I recommend between FL27 and FL31.
Being able to reach a max FL doesn't mean the plane flights there unless the weight adapts by losing Fuel, which is not at the moment. And other factors I will comment below.
Also check wind speed, wind direction, etc. I don't know if devs also use temperature (regions of the planet, hour of day, and what period it is: winter, summer, etc) and thickness of the air mass to calculate lift, which would be awesome and more realistic and would definitely influence FL for CRZ, max ceiling and N1 power for each FL.
I don't know if with all this you are satisfied, but those should be in your mind when testing.
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FYI, the Tu-134 was certified for single engine take off, so your tests aren't too crazy.
I assume you mean FL 270 and FL310. 270 is very low, I'm not aware of any jet that cruises that low.
Wind speed and direction have absolutely no effect on an aircraft in flight.
Temperature and pressure are basically the only items which affect aircraft performance.
My airplane art:
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i let the aeroplane climb up to about 20/23 or 24,000 feet (while still having a target of 33,000 set in the MCP) and engaged the CRZ thrust limit.
The FMC’s automatic power management has more safeguards than does manually activating a thrust limit.
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4deg AoA is way too high!
The 737 wing is pre-rigged at one degree of incidence and the new 737 NG/MAX aerofoil might have the Cl/Cd vs angle of attack curve peaking at less than four degrees so the cockpit AoA instrumentation display in Aerofly might not match the real thing.
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The FMC’s automatic power management has more safeguards than does manually activating a thrust limit.
Thrust limit and thrust management are two separte items. Thrust management doesn't have any safeguards concerning engine limits.
The 737 wing is pre-rigged at one degree of incidence and the new 737 NG/MAX aerofoil might have the Cl/Cd vs angle of attack curve peaking at less than four degrees so the cockpit AoA instrumentation display in Aerofly might not match the real thing.
This doesn't make sense. AoA is simply measured along the fuselage axis. At level flight AoA equals pitch attitude.
Furthermore the incidence angle and/or airfoil changes along the wingspan.
If you are flying at a 4° AoA you should significantly lower your altitude.
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Aerofly guys have a history of ‘aircraft performance bugs’ turning out to be real world phenomena
When I read that an aircraft has trouble at altitude in aerofly I am interested. Step climbs is one of my favourite things. Will be checking it out. The problem with this sim of course is you do not get the fuel burn. -
Jan’s detailed knowledge shown here is seriously impressive, he was recently working to become a gliding instructor but as is he’d do really well in much of the ATPL theory exams.
It is a pity that so many forum user’s (relatively casually) presumed Aerofly faults do get broadcast for all to see but to be fair we are all not simulating pushing a wheel-barrow, there is a lot to know about and actually getting that knowledge would be an awful lot of work.
Maybe we’ll get some serious work done on the plane’s audio and I don’t mean ATC. Having alive active sim performance and more FMC function will hopefully be nice one day but I’d like to see navigation done properly and a bigger nod towards weather coming first. -
Step climbs is one of my favourite things. Will be checking it out. The problem with this sim of course is you do not get the fuel burn.
There's nothing to check out in Aerofly. No fuel burn = no step climb. It's that simple.
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We have a full tutorial for the 737 available on our webpage
Yes, the tutorial is wrong. As you can see on this picture, taken from the tutorial, at cruise the engine mode is still at CLB shown on the middle MFD. If you select CRZ from the CDU's when you're at cruise altitude, you don't have enough thrust to substain 250 knots at reasonable altitude (FL340).
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As you can see on the flight mode annunciator the engine thrust mode is FMC SPD and the engine thrust rating limit is CLB. The engine display just shows the engine rating not the thrust mode.
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To be more precise, the CLB indication on the EICAS indicates the present thrust limit, which is correct for VNAV PTH during cruise.
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There's nothing to check out in Aerofly. No fuel burn = no step climb. It's that simple.
Fair point but there is an initial altitude for step climbs. From there you can guess the weight of the aircraft from data (something I like to do but probably of no interest to others). Every aircraft in aerofly has a weight and therefore an initial cruising altitude for the heavies. You are correct of course. no argument there
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You don't need to guess the weight.
It's essential to know it before takeoff, since you should check if the FMC computed speeds like V2, Vref etc. correct.
Since chances are close to zero that the numbers are wrong in Aerofly, you know the weight. 😉
