rennman

Low cruise speed

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She wont go above 250 kts...I think this plane is supposed to do 300kts at FL220

Both the Flight 1 and Flysimware do 300.

 

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I don't own the Alabeo one, but maybe this is a problem with the condition levers?

If taxi speed is too high when the condition levers are low and OK if they are high, maybe you need to keep them in the taxi position to get a good cruising speed?

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From what I have read, Alabeo got the condition levers wrong.  It seems that others have found that in order to taxi, the condition levers should be in high, but that means for flight they would be in low, which is not how the real Garret turbine engines work, but is how Alabeo thinks they work.

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@rennman. Confirm the condition levers are set at 96% for cruise?  (seen a few 'reviews' with the condition levers as low as 80%)

@ThomasAH. This can't be the reason as the condition levers ar e at 100% for t/o and at 96% for cruise. There's now lower setting available according to the manual. 

@stans. No, that's not how 'Alabeo thinks they work', they forgot (or are unable) to tie the actual fsx condition levers to the prop levers.

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Conquest owners group reports maximum speed 245 KIAS and cruise speed of 260 KTAS. Aviation Research states maximum cruise speed is 276KTAS. In the real world airplanes that fly a little slower than the book is not unheard of as they age. Gap seals are not as tight as they were when new, paint dulls slightly with micro scratches, engines get old and are getting closer to being temp limited, etc.

Also, there looks like two engine types the TPE331-8 and the TPE331-10 are available. The C441 does have an STC for installation of the -10 engines so what engine type is Flysimware and Flight1 modeling? 

300 KTAS sounds a little aggressive for a C441, but I am not a Conquest pilot.

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Flysimware has the -10, their manual recommends a cruise speed of 230-250 kts. (is this KIAS or TAS? I assume TAS when fully loaded)

Flight1 has the -8, their manual says Vmo is 245 KIAS.

300kts is probably TAS (ground speed with no winds).

The Wikipedia page says: 259 kts cruise speed at 35000 ft, and maximum 295 kts at 16000 ft. I guess both are given as TAS, because they are close to the TAS-values given in http://compair.aviationresearch.com/database_files/TheImage_143.pdf (259/293TAS).

And looking at the AFM for serials 441-0173 and on (but still with -8 engines) explains the small difference between Wikipedia and the linked PDF:

Speed at 8350 pounds (Speaking of pounds: Maybe you had much more fuel/payload?)

Maximum Contrinuous Powet at 16000 feet: 295 KTAS

Maximum Cruise Power at 24000 feet: 293 KTAS.

And the AFM shows 245 KIAS as Vmo, too.

So maybe the 300 (KIAS?) you see with the Flysimware is due to the more powerful -10 engines?

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The Alabeo 441 has -8 engines and according to the RW manual  max cruise at ISA is 289kts between FL180 and 200.

300kias is impossible as the 441 is VMO limited below FL100 

 

edit: just tested:  9800lbs ISA   FL200  290ktas/218kias which is within 1kt of the RW manual! 

Unfortunately testing this revealed another bug: VMO  is wrong and at FL200 it is 202kias so to cruise at the max cruising speed you have to disregard VMO...sigh....

 

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yes im talking about ground speed not IAS...sorry....both the F1 and Flysimware do 300kts ground speed all conditions being equal...the Alabeo wont go above 250

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On 3/12/2017 at 10:48 AM, KenG said:

 The C441 does have an STC for installation of the -10 engines

 

what is STC?...can i change the alabeo to the -10?

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1 hour ago, rennman said:

yes im talking about ground speed not IAS...sorry....both the F1 and Flysimware do 300kts ground speed all conditions being equal...the Alabeo wont go above 250

Ground speed is a totally useless value. It's true airspeed what you need to know.

Looks like you are doing something wrong because the Alabeo 441 does 290ktas which is exactly according to the real world performance data. 

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1 hour ago, polizei said:

Ground speed is a totally useless value

ground speed is what determines how long you trip is...not airspeed...this is essential to pilots...i dont understand your position?

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Ground speed is useless only in so far as it's variable in the real world, and in the sim depending on what weather you're running. Say you have a ground speed of 300 knots, but at the altitude you're at, the airspeed indicator is reading 250 knots. Along comes a tailwind... your indicated airspeed drops away from 250 knots, so you apply more power to keep it there. Hey presto, your groundspeed has increased. 

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6 hours ago, rennman said:

what is STC?

Supplemental type certificate. If you want an example, just let me know. Or you can google it.

brandon

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14 hours ago, rennman said:

what is STC?...can i change the alabeo to the -10?

Answered above.

Not unless you can reprogram the FDE. 

 

Groundspeed is useless in this discussion, but clearly not a useless number. Think of it this way, you race two cars but one says how fast he is going in MPH and the other how fast he is going in KPH. You can't really compare which car is faster (without converting.) In this case, we know the conversion, but when someone measures in ground speed we don't know the winds and cannot convert. Thus when talking about the maximum cruise speeds of two different aircraft we have to find a common number and that is KTAS. If you know your indicated airspeed should be right in front of you, pull out your trusty E6B and you can convert it to KTAS. (Or Google a conversion site on the internet that can perform the math for you.)

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13 hours ago, KenG said:

Groundspeed is useless in this discussion,

 groundspeed is the very issue that i began at this post....or at least meant to...but let us move on...

 

i just did a test flight...it seems engine power is not the issue...rather VNE...this plane has a lower VNE than the F1 and Flysimware versions...i will start another post about VNE...lets see if someone responds with, "VNE is useless in this discussion"  lol

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23 hours ago, HighBypass said:

Ground speed is useless

airspeed determines stall/overspeed...ground speed is what deterimines trip time...is trip time useless to pilots?...because it sure isnt to passengers

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5 hours ago, rennman said:

 groundspeed is the very issue that i began at this post....or at least meant to...but let us move on...

i just did a test flight...it seems engine power is not the issue...rather VNE...this plane has a lower VNE than the F1 and Flysimware versions...i will start another post about VNE...lets see if someone responds with, "VNE is useless in this discussion"  lol

Again,ground speed doesn't have anything to do with aircraft performance.

Before you are actually flying at your planned cruising FL and position you have no way of knowing what your actual ground speed is going to be because all you have is a theoritical forecast which usually isn't very accurate and can be totally off as well.

It's no fun having to do an unplanned refueling stop and in that case your important trip time is.....useless.

 

Another point is that there is no VNE on the C441, but VMO.

And if you re-read my previous posts in this thread you will see that I have mentioned exactly this problem already.

  

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10 hours ago, rennman said:

 groundspeed is the very issue that i began at this post....or at least meant to...but let us move on...

 

i just did a test flight...it seems engine power is not the issue...rather VNE...this plane has a lower VNE than the F1 and Flysimware versions...i will start another post about VNE...lets see if someone responds with, "VNE is useless in this discussion"  lol

 

Well then if you are looking to increase ground speed then that is simple, just find better tailwinds, you will get your 300 Knots or even better. 

Here is 350 knots in a King Air and I have done over 400. 

350%20Knot%20King%20Air_small_zps3fpelvr

Of course once that 84-knot tail wind disappeared I was back to the world of normal upper 200 knot flying. 

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10 hours ago, rennman said:

airspeed determines stall/overspeed...ground speed is what deterimines trip time...is trip time useless to pilots?...because it sure isnt to passengers

Actually exceeding the critical angle of attack determines a stall, look up an accelerated stall. Stall speed is more of a steady state fly into sort of thing used for certification and training. Stall speed and VMO is based on Indicated Airspeed and not groundspeed. You really need to read about the difference between Indicated, True and groundspeed as well as Mach number in order to have a complete understanding. The Pilot Handbook of Aeronautical Knowledge would be one reference I'd recommend. https://www.faa.gov/regulations_policies/handbooks_manuals/aviation/phak/ There are also many good articles written about this subject on AOPA. 

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14 hours ago, KenG said:

Actually exceeding the critical angle of attack determines a stall

because it reduces airspeed...

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without getting sidetracked into a discussion of basic aerodynamic science...i have confirmed that the Alabeo 441 has a much lower VNE than the Flysimare 441...

Alabeo barber poles at 190 kts (@FL220)

Flysimware barber poles at 220kts (FL220)

problem is...they both cant be right

this is how i have faster groundspeed with the flysimware...which for me is valuable...but of course...the Alabeo is of much higher quality...but slower

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2 minutes ago, rennman said:

without getting sidetracked into a discussion of basic aerodynamic science...i have confirmed that the Alabeo 441 has a much lower VNE than the Flysimare 441...

Alabeo barber poles at 190 kts (@FL220)

Flysimware barber poles at 220kts (FL220)

problem is...they both cant be right

this is how i have faster groundspeed with the flysimware...which for me is valuable..

the Alabeo is of much higher quality...but slower

 

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On 3/22/2017 at 8:47 PM, rennman said:

because it reduces airspeed...

This is from the document (page G-28) I provided you and is the FAA definition of a stall.

Quote

Stall. A rapid decrease in lift caused by the separation of airflow from the wing’s surface, brought on by exceeding the critical angle of attack. A stall can occur at any pitch attitude or airspeed.

1

Go find another CFI, CFII, MEI to argue this with. Clearly, you have incorrectly decided that you know everything about aviation and no one (not even certified professionals) can tell you otherwise. 

You can be ignorant, but when you decide to double down on ignorance that is just being stupid.

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Here's something - might be a bit random, but maybe not :)

I have a freeware IL-76 - The instrument panel supplied with it had lots of missing gauges seeing as I didn't have loads of old ones installed from FS9 etc. I went looking for another panel- the closest I found which looked  - kind of, sort of like the Ilyushin's was one for a Comet 4. However the aircraft overspeeded (oversped??) due to the panel barber pole being set at M 0.76 or some such. The IL-76 can fly at M0.82 according to some internet. I edited the aircraft.cfg to raise the max speed and the barber pole on the gauge changed accordingly - no overspeed at normal Mach number for the plane. 

Alter the Alabeo aircraft cfg file maybe?

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