This preview shows pages 1–2. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: Unified Engineering I Fall 2003 Problem S12 (Signals and Systems) The longitudinal dynamics of an aircraft ying are given in statespace form as dh dt = V sin (1) dV T D dt = g sin + m m (2) d dt = L mg mV (3) where h = altitude V = velocity of aircraft = ight path angle g = acceleration due to gravity L = lift T = thrust D = drag m = mass of aircraft We assume that (1) the thrust is constant, (2) the aircraft ies at constant coeeficient of lift, and (3) the aircraft ies at constant drag coeeficient. These assumptions are not bad for the case whent he pilot releases all the controls, and makes no adjustments, say, for altitude variations. In this case, we can rewrite the equations as dh = V sin (4) dt dV T D 0 V 2 = g sin + (5) dt m m V 2 d L ( V/V ) 2 mg = (6) dt mV where L 0 and D 0 are the lift and drag at the nominal velocity, V . If the aircraft is intially in trim, it must also be true that T = D 0 (7) L 0 = mg (8) Equations (4)(6) are the equations of motion in statespace form, although the...
View Full
Document
 Fall '05
 MarkDrela
 Dynamics

Click to edit the document details