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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