https://docs.zoho.com/sheet/publishe...49361bf72180d6

In the above stability spreadsheet Raghu calculates the tail contribution as:

C_tail =L2*J2*K2/(iyy*391*1.46) (cell G5)

The numerator is the tail volume times the HS lift curve slope. Iyy is the mass moment of inertia. Can someone shed some light on why the two constants 391 and 1,46 are needed?

PS: I have developed a stand alone version of the spreadsheet which I would make available if Raghu has no objections. It would, of course, contain a link to his original work. Looking forward to your answer Raghu, if you happen to read this.

In the above stability spreadsheet Raghu calculates the tail contribution as:

C_tail =L2*J2*K2/(iyy*391*1.46) (cell G5)

The numerator is the tail volume times the HS lift curve slope. Iyy is the mass moment of inertia. Can someone shed some light on why the two constants 391 and 1,46 are needed?

PS: I have developed a stand alone version of the spreadsheet which I would make available if Raghu has no objections. It would, of course, contain a link to his original work. Looking forward to your answer Raghu, if you happen to read this.

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