If the engine was placed such that it was aligned with the longitudinal axis of the aircraf, it would either need to be installed on a pylon to lift it above the fuselage like in the case of Flaris LAR 1, or it would need to be placed inside the fuselage, necessitating ducting like in the case of Stratos 716X The placement of the engine avoids the need to use ducting or a pylon. Shown here, in this reference, is the actual configuration of the air intake and engine.Īs I read it, the question is asking about the engine installation: why is it placed in the way it is? This is where the line of the nacelle may be a bit deceiving. Indeed, many jets have S-shaped inlets (which may help for birdstrikes). The engineers may have tweaked the exhaust angle to get it just right.įinally, it should be noted that the angle of the intake is not necessarily directly in line with the combustion chamber and exhaust of the jet. One might note the exhaust stream across the tail may have been somewhat unpredictable in design, with either an increase in pitch down due to Coanda effect or a pitch up due to higher pressure in the exhaust stream than surrounding air. The angling of the exhaust may have been added to fix an excessive pitching tendency. Downward pitching thrust moment helps avoid power on stalls by helping to control this tendency, Just as engines fore of the CG are pitched down to create a nose-down pitch torque when thrust is added, rear mounted engines can be pitched up to create the same effect.Īdding thrust adds speed, which adds lift, causing the plane to pitch up. This is somewhat beneficial for speed handling. SF50 was created largely for relatively inexperienced first-time jet pilots, and its handling must be fairly straightforward.ġ But still, it seems, slightly higher (esp. 1 This creates minimal pitch disturbances due to thrust changes. This makes the thrust line pointing 5.47° down, thus overcompensating the engine alignment.įrom the same link provided in the Koyovis's answerĪs a result, the thrust line passes fairly close to the centre of mass. The exhaust nozzle is tilted a whopping 14° with respect to the engine centreline (data from FJ33-5A IOI (Installation/Operation Instuctions)). The engine is partially buried in the fuselage. This is a bit less than what it visually seems from the nacelle, due to the flattened intake. Basically, it's just a reasonable compromise for a compact single-engine passenger jet.Īs for the mitigation part, I happen to know some data.
There are two questions here: why so and how is it handled.įor the first one, I'll refer to the Jpe61's answer.
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