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martino2706

speed

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Any time. Also, please try to ignore smartassery in the forum. Folks are rather mean to newcomers here for some reason. I suppose they were all born knowing everything about aviation.

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To be fair, there was only one unhelpful reply. Most were trying to help.

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Dan Downs KCRP

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48 minutes ago, icemarkom said:

Any time. Also, please try to ignore smartassery in the forum. Folks are rather mean to newcomers here for some reason. I suppose they were all born knowing everything about aviation.

I'm not really too sure what was wrong with my post. All I asked was what his Mach speed was. Knowing that goes a long way to knowing whether there's actually an issue or not.

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Captain Kevin

nGsKmfi.jpg

Air Kevin 124 heavy, wind calm, runway 4 left, cleared for take-off.

Live streams of my flights here.

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2 hours ago, Captain Kevin said:

I'm not really too sure what was wrong with my post. All I asked was what his Mach speed was. Knowing that goes a long way to knowing whether there's actually an issue or not.

I think it was the fact that you asked what his Mach speed was when he didn't even know what IAS was. It could come off as rude asking that when he didn't even know the basics with absolutely no chance of him knowing what it means, let alone where to find it on the PFD.

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15 hours ago, martino2706 said:

thanks to all of you

I read the above, sorry if I missed it - but I didn't see the layman explanation. Marko's explanation makes perfect sense, but its still pretty technical.

martino2706 - if you're at 35,000 and the "speed" in your cockpit is showing 280 (or 298 in the photo below), for a variety of reasons (explained above) you are actually travelling much much faster. If you had a car following you on the ground, it would be traveling about 420.

You can see this in your cockpit. The speed on the "tape" is the IAS, the one that seems low to you. If you look right can see the actual ground speed (the speed at which the car on the ground following would have to be going in order to keep up with you). That speed is shown in the upper left of the navigation display (window to the right).

I would encourage you to research the internet over time to gain knowledge about flight dynamics. Not sure how old you are, but if you are still very young a lot of the concepts will go right over your head until you've had a chance to take physics in high school - and maybe if you go to college some fluid dynamics will clear things up. Otherwise, if you're just dinking around with the flight sim and want answers now, hopefully this clears things up.

x3jzTFu.jpg

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Also, in the above screenshot, the Mach speed is what you want to look for, which in this case is Mach 0.850. As long as you're doing that speed, you're fine.

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Captain Kevin

nGsKmfi.jpg

Air Kevin 124 heavy, wind calm, runway 4 left, cleared for take-off.

Live streams of my flights here.

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M0.85 in a NG? Bit behind schedule were we? 


Cheers,
Ryan

Professional Coffee Drinker/BAe146 Driver
Aircraft Maintenance Engineer

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25 minutes ago, NJ_Flyer said:

M0.85 in a NG? Bit behind schedule were we? 

Funny!  But Kevin was referring to the screen shot just above his post.  I don't think we know which aircraft the OP is flying, and it doesn't matter for his question.

 

On 8/1/2017 at 5:40 PM, Captain Kevin said:

I'm not really too sure what was wrong with my post. All I asked was what his Mach speed was. Knowing that goes a long way to knowing whether there's actually an issue or not.

Kevin, I don't think anyone was referring to your post.

Mike


 

                    bUmq4nJ.jpg?2

 

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13 hours ago, NJ_Flyer said:

M0.85 in a NG? Bit behind schedule were we? 

Gave me a good chuckle but Nick's image is the 777 I believe.

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A proper layman's answer is that you need a certain amount of air to pass over (and under) your wings to keep flying. At sea level, that is the same as the amount you get flying at 280 knots. As you go higher, the air gets thinner but the clever thing about the way they measure IAS is that it will still say 280 when you have the same amount of air, no matter how thin it gets.  That is why they measure it that way.

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On 02/08/2017 at 6:16 AM, martino2706 said:

hi. why is mine max crz speed only 280?

Hi Martino,

I hope you have learnt why the speed on the PFD is different to your actual speed.

I am making an assumption here, but if you are new to Flight Sims (or Boeings), I highly recomend you watch some youtube tutorials regarding how to operate these beasts. :) 

 

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I would like to add that, the reason the IAS is so prominently displayed is because of its critical importance- as the IAS (Indicated Air Speed) approaches your aircraft stall speed, you will enter a stall and begin a rapid decent.  From a pilot's perspective, the IAS is one of the most important numbers in the entire cockpit- it dictates when you have enough air molecules flowing over the wing to takeoff, and when you've flown so high that the air is so thin that your IAS is approaching your stall speed.

Your IAS is what keeps you alive.  If for some reason you were flying 150 IAS and you got hit with a tail wind of 50 knots, your IAS would fall to 100.....and you'd fall out of the sky like a lead balloon.  But if your eyes were merely focused on (GS) Ground Speed alone, you'd slam into the ground wondering how you could have a ground speed well above stall, and yet still falling.

Just wanted to explain why IAS is such an important number - air over the wings is a critical component to measure and it varies by temperature and altitude.

Mark Trainer

 

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On ‎8‎/‎3‎/‎2017 at 7:35 PM, NJ_Flyer said:

M0.85 in a NG? Bit behind schedule were we? 

Must be "go-home day"...:biggrin:


David Rosenblum

Atlas Air Boeing 767 Captain; previously a Boeing 747-400/-8 First Officer

Jetline Gravity GTX | Aorus Z370 Gaming 7 motherboard | i7 8700K overclocked to 5 GHz | 32GB 3 GHz Corsair DDR4 SDRAM | 11GB GTX 1080 Ti | 1TB Samsung 960 Pro m.2 SSD | 2TB WD Black 7200 RPM SATA 6.0Gb/s HDD | Corsair Hydro H100i v2 Dual Stage Liquid Cooling | 3 Dell S2716DG G-Sync monitors on Jestik Arc stand | Thrustmaster HOTAS Warthog | Logitech G Saitek Pro Flight Yoke System, Throttles and Pedals

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