Balance point and calculated index

[iGoApp]

Jagipson, you beat me on that one! :-)

Do you use speed correction based on temp and altitude? Also, do you estimate the runway length based on wet vs dry conditions? Also, in Main Calculations worksheet, I entered Fuel on board of 8000, and it shows me %MAC and Stab Trim for LW (actual) as #N/A. There may be some error in the formula. Otherwise, great work!

Edited November 15, 2012 by igorland

[jagipson]

Hi Jagipson.

Can't load it. As the previous version, can you edit an xls one ?

Anyway, nice job.

Do you mean you could not open either this version or the previous version of the spread sheet? Did you press the "Use This Template" button? Can you priv msg me a screen shot?

[jagipson]

Jagipson, you beat me on that one! :-)

Do you use speed correction based on temp and altitude? Also, do you estimate the runway length based on wet vs dry conditions? Also, in Main Calculations worksheet, I entered Fuel on board of 8000, and it shows me %MAC and Stab Trim for LW (actual) as #N/A. There may be some error in the formula. Otherwise, great work!

I'm not sure where you are referring to a Speed Correction. Can you tell me the sheet name and Cell address?

Also the #N/A in Cells E35 and F35 can happen if the value you enter for Fuel at TOD (cell C34) is greater than the initial fuel (C28). This can only happen if you did mid-air refueling. See if that's the problem.

[iGoApp]

I'm not sure where you are referring to a Speed Correction. Can you tell me the sheet name and Cell address?

For example, Vspeed correction at 2000 ft and 30 C is +2 (18000 kg). If V1 = 122, the corrected speed should be 124. Is this right? So, I was just asking whether your calculated speeds take that into account. Cheers.

Edited November 16, 2012 by igorland

[birdy.dma]

Do you mean you could not open either this version or the previous version of the spread sheet? Did you press the "Use This Template" button? Can you priv msg me a screen shot?

Ok. It is the first time i use the google thing. Thanks.

[jagipson]

For example, Vspeed correction at 2000 ft and 30 C is +2 (18000 kg). If V1 = 122, the corrected speed should be 124. Is this right? So, I was just asking whether your calculated speeds take that into account. Cheers.

Ah, the V-Speeds. That functionallity was on the original spreadsheet that came with the plane, and I just ported it to Google Spreadsheet. They do _not_ appear to adjust for ISA conditions or altitude. I'd be happy do make this modification if someone can tell me how to determine the ISA adjustment from METAR data.

[iGoApp]

If you can open my spreadsheet, you will see how I did it (you need to unhide the hidden spreadsheets). i also calculated the runway length based on the dry-wet condition. Getting these data (temperature and runway condition) from the metar may be tricky. If you get it as fixed width text, you could perhaps do the text to columns function and then use the appropriate column for the value determination. Do I make sense?

Edited November 16, 2012 by igorland

[jagipson]

If you can open my spreadsheet, you will see how I did it (you need to unhide the hidden spreadsheets). i also calculated the runway length based on the dry-wet condition. Getting these data (temperature and runway condition) from the metar may be tricky. If you get it as fixed width text, you could perhaps do the text to columns function and then use the appropriate column for the value determination. Do I make sense?

I have no Excel so I can't even open your spreadsheet

However, I have just released Version 4.0 which incorporates all the tables from the POH and it now calculates using the Vspeed Corrections. The way I implemented this was to add all the VSpeed Correction tables for each weight class (lots of typing) and perform a series of lookup functions to grab the right values. The corrections are then added to the 8 degree and 20 degree V1 and VR values on the main calculations sheet.

Grab the new version here:

http://drive.google.com/templates?q=crj200

I don't see a calculation for wet vs. dry runway length in the POH. Where is that from?

[iGoApp]

The way I implemented this was to add all the VSpeed Correction tables for each weight class (lots of typing) and perform a series of lookup functions to grab the right values. The corrections are then added to the 8 degree and 20 degree V1 and VR values on the main calculations sheet.

...

I don't see a calculation for wet vs. dry runway length in the POH. Where is that from?

1) Yes, this is also how I did it.

2) CRJ Pilot Handbook 1.0.1. Landing distance -- p.23; Wet landing field length -- p. 24. But this is not really important.

3) It is hard to make perfect better, but in this case you may add the last thing -- Reduced Thrust Take-Off Setting, unless I miss it somewhere. :-)

Great work! You should upload it to the org site, I think there is appetite for that. If I ever finish my java self-learning, I wanna try to do it in java as a pilot project. May be when I am retired and have a bit more time...

Edited November 17, 2012 by igorland

[jagipson]

Isn't reduced thrust TO setting done automatically by the FMC on the PERF page when entering the temperature?

[iGoApp]

Isn't reduced thrust TO setting done automatically by the FMC on the PERF page when entering the temperature?

I never tried it! Always manually entered the limit using the reference table. Never mind then. Cheers for your work!

[jagipson]

I never tried it! Always manually entered the limit using the reference table. Never mind then. Cheers for your work!

Nevertheless, I've just added it. Dry runway requirement was already on the Main Calculation sheet at the very bottom. I have added Wet. Thanks for the feedback.

[Kyle Sanders]

jagipson,

I have been searching since the initial release if the JR CRJ2 for exactly what you guys are doing!!!! Thank you so much!

May I get the link to your most up to date planning sheet? I see that you have updated it to display wet vs dry but I don't see a link to the updated version.

I am on my cellphone right now and can't open any if them- are they all the same link and is just continued to be updated automatically?

[Kyle Sanders]

Sir,

Please forgive my previous, Stupid question about the updated Spread Sheet.

 

I really like what you have done with the CRJ Spread Sheet.

 

I have attached the picture of the first page of a REALLY great manual I have got my hands on.

 

I think you could use it. The agreement is that you do not share it with anyone. You keep it private. Please let me know if you agree to this and I will send the 70mb document via a DropBox link.

 

I have noticed that your spreadsheet is only missing 2 things.

1) Optimum Cruise Altitude Selection calculation. (AKA- "LRC")

2) Speed calculations.

 

Both of these tables are found in the manual I have. Please let me know if you are interested.

[iGoApp]

Hi, jagipson. I think there is an error in your table: cell I7 in table DATAREF should be 0. Cheers,

Edited December 12, 2012 by igorland

[Vantskruv]

I did extract some equations from the spreadsheet and simplified them at Wolfram Alpha.

To get the X-Plane CG value (if this is still correct...):

Kilos as ZFW:

CG = ( (11.2754*LIZFW - 561.288) / (ZFW + 0.36) ) + 7.95301

LBS as ZFW:

CG = ( (24.8579*LIZFW - 1237.43) / (ZFW + 0.793665) ) + 7.95301

where which ZFW is divided by 1000.