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avatar+1037 
+10

$$\text {The lift equation } \ C_L \;=\; C_L_\alpha \; + \; \alpha \;+ \; C_{L_0}
\\
\\ C_L_\alpha \; = \; \dfrac {0.052 -0}{5-(-1.5)}\rightarrow C_L_\alpha \; = \; 0.08 / Deg. \rightarrow \\\
\ C_{L_0} \; = \; (0.08)(1.5)\; = \; 0.12 \\\
\text {The moment equation } C_M \; = \; C_M_\alpha \; + \; C_{M_0} \\
\ C_M_\alpha \; = \; \frac {0.05 -(-0.01)}{7.88-1}\; = \; 0.0087 / Deg.\rightarrow \\\
\ C_{M_0} \; = \; (0.0087)(-1) \; +0.01 \; = \; -0.0187 \\\
\text{Use results from above in equation below for } C_M \text{ as a function of } C_L \\
\ C_M (\alpha) \; = \; \Bigg (\dfrac {C_M_ \alpha}{C_L_\alpha}\Bigg ) \; C_L \; - \; \Bigg ( \Bigg(\dfrac {C_M_ \alpha C_{L_0}}{C_L_ \alpha} \Bigg ) \; - \; C_{M_0} \Bigg ) \rightarrow \\
\ C_M (\alpha) = \; \Bigg(\dfrac {(0.0081)}{0.08} \Bigg ) \; C_L \; - \; \Bigg ( \Bigg(\dfrac {(0.0081)(0.012)}{0.08} \Bigg ) - (-0.0187) \Bigg ) \\\\
\ C_M (\alpha) = \; 0.1087 C_L \; -\; 0.0318 \rightarrow
\\
\ C_M \; = \; 0.0318
\\\\
\text { The aerodynamic center is } \ 0.035 \; + \; 0.0318 \; = \; 0.0668 \\$$

 

This aircraft is not stable. The center of gravity is aft of the neutral point (based on

$$C_{M_0} \; = \; (-0.0187)\\

\
\\$$

 

This may be “normal” for a Harrier type jet.

More likely I have been breathing too much Ozone from the Special NaClO3. This may not be correct. Mayday! Mayday! Mayday! Someone needs to apply the dumbness correction factor(s) to compensate for the remnants of my CDD.

Alan can solve this before his morning tea finishes brewing.

Nauseated Dec 21, 2014
 #194
avatar+93289 
0

Mon 22/12/14

1)  Great Puzzle - We always like puzzles to be shared.  Thanks Anon and Geno.

http://web2.0calc.com/questions/here-is-a-riddle-that-i-ve-heard-long-time-ago

2)  I did like CPhill's fun answer here.  Thanks Chris.  

http://web2.0calc.com/questions/how-many-people-can-i-feed-with-3-pounds-of-fudge

3)  Chrismas Songs - Jillybean would like you to share your favourite christmas songs with her. 

Thanks Jillybean and Chris.    

http://web2.0calc.com/questions/holiday-songs

4)  Physics - Thanks Nauseated but you do not seem to sure of your answer. I wonder if it is correct?  

http://web2.0calc.com/questions/right-lets-see-whos-clever-enough-to-answer-this

5)  Physics - Thanks Alan

http://web2.0calc.com/questions/physics_70#r1

6)  A really good indice answer.   Thanks anon  

http://web2.0calc.com/questions/0001-raised-to-25-power

7)  The trig bearings question really tested my abilities with geogebra.  It is a good question too.  

 http://web2.0calc.com/questions/three-airports-a-g-e-forms-a-triangle-airport-g-has-a-bearing-of-52-degrees-to-airport-a-airport-a-has-a-bearing-of-216-degrees-to-airpo

                ♫♪  ♪ ♫                                ♬ ♬ MELODY ♬ ♬                                 ♫♪  ♪ ♫

Melody Dec 21, 2014
Dec 20, 2014

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