What’s the horizontal tail volume coefficient of 747-400? What’s the vertical tail volume coefficient of 747-400? What’s the horizontal tail airfoil of 747-400? What’s the vertical tail airfoil of 747-400?
How can I find these specifications? I can’t find it anywhere. Is it some sort of calculation I’m supposed to make??
This sort of data is incorporated in the aeroplane pre-design textbooks. The one I have is Synthesis of Subsonic Airplane Design by Torenbeek, which unfortunately predates the B747-400. But there is data available for the B747-100/200, in sections 9.5 9 Preliminary Design of the Horizontal Tailplane and 9.6 Design of the Vertical Tailpllane.
Table 9-2 lists a.o. the following parameters for the B747 100/200 horizontal tailplane:
And from table 9-3 the data for the vertical tailplane:
Airfoil sections for other aeroplanes of the era are listed in the table, also referenced in this answer, but not for the B747. Profile type must have been a closely guarded secret at the time already.
You can calculate the said coefficients after you google the needed dimensions for 747-400.
From EAA chapter 62 website "How Big The Tail by Stan Hall:
The Tail Volume Coefficients relate the area of the surface, the distance that area is from the aircraft's c.g., the wing area, the mean aerodynamic wing chord and the wing span.
In equation form Horizontal Tail Volume Coefficient (VH) looks like this.
VH = SH x LH / SW x m.a.c.
where SH = horizontal tail area, LH = distance from tail's aerodynamic center (more of which later) to the aircraft c.g., SW = wing area and m.a.c = the mean aerodynamic chord (more of this later, too)
For the Vertical Tail Volume Coefficient (VV) the equation looks like this.
VV = SV x LV / SW x b
where SV = vertical tail area, LV = distance from the vertical tail's aerodynamic center to the aircraft c.g., SW = wing area and b = wing span.
