The military jet aircraft has a gross weight of \(24,000 \mathrm{lb}\) and is poised for takeoff with brakes set while the engine is revved up to maximum power. At this condition, air with a specific weight of \(0.0753 \mathrm{lb} / \mathrm{ft}^{3}\) is sucked into the intake ducts at the rate of \(106 \mathrm{lb} / \mathrm{sec}\) with a static pressure of \(-0.30 \mathrm{lb} / \mathrm{in} .^{2}\) (gage) across the duct entrance. The total cross-sectional area of both intake ducts (one on each side) is \(1800 \mathrm{in} .^{2}\) The air-fuel ratio is 18 , and the exhaust velocity \(u\) is \(3100 \mathrm{ft} / \mathrm{sec}\) with zero back pressure (gage) across the exhaust nozzle. Compute the initial acceleration \(a\) of the aircraft upon release of the brakes.

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