capt.arab

PMDG 777-200

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Hi guys,,

 

I have been trying my best to figure out my issue since i have found this.

I flying now OEJN to KJFK 

Jeddah Saudi Arabia to New York 

Real time flying ours is 13Hrs 

On my sim it is 18 flying hours.

 

How could it be this far since i am using actual RTE of 5673 Nautical miles i found that with the converting ecuagen 5673÷303= 18.7Hrs

 

 

thnc

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39 minutes ago, capt.arab said:

On my sim it is 18 flying hours.

 

How could it be this far since i am using actual RTE of 5673 Nautical miles i found that with the converting ecuagen 5673÷303= 18.7Hrs

 

Well It seems the number your using for your GS is way off.  Did you do the flight in 18 hours or is the simulator telling you its going to be 18 hours.  Because if its the sim reason its so far off is because the planned TAS is probably wrong.  A 777 will cruise TAS around 450-480 Kts (I'm unsure of the exact number).  Adjust this for wind and you have your ground speed.  So until your fighting a 180 kt head wind that 303 is way off the mark.

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57 minutes ago, capt.arab said:

How could it be this far since i am using actual RTE of 5673 Nautical miles i found that with the converting ecuagen 5673÷303= 18.7Hrs

 

Where did you get "303" from?

Mike

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22 minutes ago, Mike777 said:

 

Where did you get "303" from?

Mike

Flight speed 

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37 minutes ago, thibodba57 said:

Well It seems the number your using for your GS is way off.  Did you do the flight in 18 hours or is the simulator telling you its going to be 18 hours.  Because if its the sim reason its so far off is because the planned TAS is probably wrong.  A 777 will cruise TAS around 450-480 Kts (I'm unsure of the exact number).  Adjust this for wind and you have your ground speed.  So until your fighting a 180 kt head wind that 303 is way off the mark.

I calculated the total nautical miles devided by airspeed. 

 

Head wind 234/ 56

at gs 481 

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I think you are confusing "Indicated Airspeed (IAS)" with "True Airspeed (TAS)".  The IAS shows on the left of the PFD and will decrease as you climb, but the TAS and the Ground Speed (GS) are indicated on the Navigation Display upper left corner.

Mike

 

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Mike has it right.  Ground speed is the result of adjusting True Airspeed for the affects of wind.  Indicated Airspeed is affected by the air mass outside the aircraft and therefore decreases in altitude thus is not a source for navigation.

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Which speed did you take for the calculation? There were several topics about the time was off but all of them were because of calculation from IAS (from the PFD). 777 has much higher GS than that unless you have ~150kts or more headwind.
Hoang Le

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I can never understand why people want to jump into complex airliners if they have absolutely no idea about the basics of the theory of flight.

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8 minutes ago, ErichB said:

I can never understand why people want to jump into complex airliners if they have absolutely no idea about the basics of the theory of flight.

+++1

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When you divide 5673 NM by 0.84 you get  6753.... minutes or hours or days, don't know.... which is even more :-)

 

What you are interest in is like all others said: Groundspeed. Then you will get the right flight duration.

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That there is todays Saudia 21 flight.  Its been filed as 12 hours and 16 mins.  Using a cruise speed across the pond on track C at Mach 84 .  

  The Saudi's have got plenty of petro dollars.  So crank the speed up to m.84.  And remember dont  open the bars until you reach egypt 57 minutes into the flight.

(FPL-SVA021-IS
-B77W/H-SDE2E3FGHIJ4J5M1RWXYZ/HD1
-OEJN0430
-N0516F280 MIGD1N MIGDA L677 RIDEP/N0513F300 L677 CVO A16 RASDA UM855 KFK UL619 MAKOL L619 BUKEL/N0494F320 L619 KARIL DCT KENIN DCT LENOV L619 DENKO L996 VAVUN M602 BINKA DCT SONAL M602 ROBUS L983 GOMOT/N0497F340 L983 MADAD P58 FINDO DCT GOMUP/M084F340 NATC HOIST/N0489F340 N602A COVAN DCT ALB DCT IGN IGN1
-KJFK1216 KEWR
-PBN/A1B1C1D1O1 NAV/RNP1 RNP2 RNP5 RNP10 RNVD1E2A1 DAT/SV DOF/170727 REG/HZAK38 EET/HECC0057 LCCC0146 LTAA0206 LTBB0228 LBSR0249 LRBB0307 LHCC0340 LZBB0345 EPWW0353 EDUU0441 EKDK0451 EGPX0525 EGGX0631 020W0713 CZQX0750 040W0826 050W0904 ADIZ0918 CZQX0934 HOIST0936 CZUL1021 KZBW1129 KZNY1202 SEL/EFAB ORGN/OEJNZPZA PER/D RALT/EINN CYYR RMK/TCAS EQUIPPED)

where your getting 18 hours from I dont know.

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Wow guys be nice.  While you guys might not have any idea why some people jump directly into a jet with understanding the fundamentals. I don't understand why people feel the need to jump down people's throats and mock them rather than teach them.  If your not planning on being constructive just move on please.  Aviation sim groups are some of the most hostile groups on he net.  This just proves it.  Aviation is very complex and takes YEARS to learn.  Not a single one of you knew the difference between IAS and TAS at the beginning either.

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35 minutes ago, thibodba57 said:

Wow guys be nice.  While you guys might not have any idea why some people jump directly into a jet with understanding the fundamentals. I don't understand why people feel the need to jump down people's throats and mock them rather than teach them.  If your not planning on being constructive just move on please.  Aviation sim groups are some of the most hostile groups on he net.  This just proves it.  Aviation is very complex and takes YEARS to learn.  Not a single one of you knew the difference between IAS and TAS at the beginning either.

This is not about aviation details - this is about absolut basics. Just saying :-)

And people here clearly laid out the difference between IAS / GS etc. Just a little bit of research would have done the trick.

 

But you are right,sometimes people in here are a little bit impolite. But so is asking questions which can be answered by 1 minute googling and 3 minutes reading...

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When I was a student my instructor didn't tell me to Google it. Of course you could only get on the net by modem then and we didn't have all the resources we have now.  But I certainly wouldn't tell my students now to Google it because it was the basics. I would explain the differences and we would move onto the next subject matter.

I mean after we explained the differences he stopped posting.  Then everyone dog piled on him mocking him.  There was absolutely no call for any of that.  The guy only has 10 posts so is obviously new and everyone is going to run new people off if we treat people this way.  And this hobby needs every person we can get.

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2 hours ago, thibodba57 said:

Wow guys be nice.  While you guys might not have any idea why some people jump directly into a jet with understanding the fundamentals. I don't understand why people feel the need to jump down people's throats and mock them rather than teach them.  If your not planning on being constructive just move on please.  Aviation sim groups are some of the most hostile groups on he net.  This just proves it.  Aviation is very complex and takes YEARS to learn.  Not a single one of you knew the difference between IAS and TAS at the beginning either.

I'm guilty of that and I apologise to the OP.

However.  Culinary french cooking is also highly complex and takes many years to master.  What the OP has asked is the equivalent of me asking why my souffle hasn't puffed because I used 2 eggs and a spoon of flour (because it's that simple, right?) -  while my actual culinary skill starts and ends with making toast.   

The answer to what the OP has asked, requires the grasp of a number of basic physics/science fundamentals (as you well know).  I spent many years flying more basic aircraft and grasping basic principles before I even bought my first PMDG aircraft. I never assume anything is as easy as it seems and I can't particularly enjoy doing something if I don't really understand what I'm doing.   But that's just me.  Break it down and start at the beginning - I've always maintained that.  You learn alot more that way, and those who actually want to learn will understand that point.

I agree that sometimes the Avsim forums come across as a bit of a niche club - and I hate that kind of thing myself so I apologize if I've contributed to that view.  It wasn't meant that way.

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Equally valid counter-argument, Erich.

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But unlike the realworld you step into flightsim unaware of the complexities and can jump into something way over your head and not know why.  You don't now even know there is such a thing as TAS, IAS or GS or their differences.  How could you? So it's up to us to help people out that have zero understanding of what's what and not mock them.  What you seem to be expecting people todo is open up the Jepp Private Pilot Manual (880 pages) before they jump into something.  NO ONE and I mean NO ONE did that before taking a spin in the sim.  You'd be bored by the end of the first chapter and never turn the program on.

It would be like me mocking you for not doing your research and failing to program your VNAV profile to an NADP-1 close in or NADP-2 distant departure. I'm willing to bet half or more don't even know what those are and just let the default programming stay in CDU.  But I don't EXPECT people to know what those are or even exist and won't mock them for not knowing.  It's why we have a community so we can all learn and move forward together.

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3 minutes ago, thibodba57 said:

But unlike the realworld you step into flightsim unaware of the complexities and can jump into something way over your head and not know why.  You don't now even know there is such a thing as TAS, IAS or GS or their differences.  How could you? So it's up to us to help people out that have zero understanding of what's what and not mock them.  What you seem to be expecting people todo is open up the Jepp Private Pilot Manual (880 pages) before they jump into something.  NO ONE and I mean NO ONE did that before taking a spin in the sim.  You'd be bored by the end of the first chapter and never turn the program on.

It would be like me mocking you for not doing your research and failing to program your VNAV profile to an NADP-1 close in or NADP-2 distant departure. I'm willing to bet half or more don't even know what those are and just let the default programming stay in CDU.  But I don't EXPECT people to know what those are or even exist and won't mock them for not knowing.  It's why we have a community so we can all learn and move forward together.

I couldn't have said it better, except that I have no idea what NADP-1 and NADP-2 departures are!

Of course now that I've heard of them I can google them!  But I don't see how the OP could have googled a distinction of which he was unaware.

Mike

 

 

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25 minutes ago, Mike777 said:

I couldn't have said it better, except that I have no idea what NADP-1 and NADP-2 departures are!

But I don't see how the OP could have googled a distinction of which he was unaware.

Mike

 

 

And this is exactly my point.  How is anyone supposed to learn the differences if they don't even know that there is supposed to be a difference.  I think a lot of people need to think back here and realize they didn't come into this hobby knowing everything and they had A LOT of learning todo along the way.  And as is the truth in everything in life there are still tons of things they don't know and need to learn.

BTW, https://www.icao.int/environmental-protection/Documents/ReviewNADRD.pdf   General jist, close in (NADP1) 3000 AFE accelerate 1500 AFE Thrust reduction, Distant (NADP2) 1000 AFE Accelerate and Thrust reduction at some other predetermined point (747 Flaps 5).

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Thank you guys anyway i have figured how much help i can get from u ( some ) but the others if you are not intrested to help please keep your nice fingers relaxed instead of typing some good words you can save for tour selves.

 

 

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26 minutes ago, capt.arab said:

Thank you guys anyway i have figured how much help i can get from u ( some ) but the others if you are not intrested to help please keep your nice fingers relaxed instead of typing some good words you can save for tour selves.

 

 

If you are calculating the time yourself, by dividing total distance by the airspeed shown on the pilot's flight display, it will give you a false result. As some others have pointed out, that airspeed reading will be much lower than your true airspeed when flying at high altitudes.

The actual time enroute is available on the FMS progress page. This page will predict the time (in UTC) that you will arrive at your destination, and is continuously updated as you fly. The FMS knows how much distance is remaining to the destination at any given moment, and also knows your true airspeed and ground speed. On a long flight, the predicted arrival time may change somewhat as your ground speed changes due to headwinds and tailwinds - but it is usually reasonably accurate.

No need to calculate by hand - the FMS will do this for you.

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