dc = (te * pg) + ev
-----------------------------------
dc - deceleration (km/hr)
te - time from entry of gravitational field (hr)
pg - planetary gravity (km/(hr**2))
ev - entry velocity (km/hr)
-----------------------------------
Deceleration needs to be such that the shuttle's velocity reaches zero before reaching the planet surface.
-This might lead to a maximum transit speed to allow for a safe landing.
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cs = fs + (t * ac)
-----------------------------------
cs - current speed (km/hr)
fs - former speed (km/hr)
t - time (hr)
ac - acceleration (km/(hr**2))
-----------------------------------
While fs <= sl
	sl - speed limit
	-determined by how much time will be needed to stop the ship in time for landing
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