An aircraft is trimmed straight and level at true air speed (TAS) of $100 \mathrm{~m} / \mathrm{s}$ at standard sea level (SSL). Further, pull of $5 \mathrm{~N}$ holds the speed at $90 \mathrm{~m} / \mathrm{s}$ without re-trimming at SSL (air density $=1.22$ $\mathrm{kg} / \mathrm{m}^{3}$ ). To fly at $3000 \mathrm{~m}$ altitude (air density $=0.91 \mathrm{~kg} / \mathrm{m}^{3}$ ) and $120 \mathrm{~m} / \mathrm{s}$ TAS without re-trimming, the aircraft needs
(A) $1.95 \mathrm{~N}$ upward force.
(B) $1.95 \mathrm{~N}$ downward force.
(C) $1.85 \mathrm{~N}$ upward force.
(D) $1.75 \mathrm{~N}$ downward force.

Question ID - 156241 | SaraNextGen Top Answer

An aircraft is trimmed straight and level at true air speed (TAS) of $100 \mathrm{~m} / \mathrm{s}$ at standard sea level (SSL). Further, pull of $5 \mathrm{~N}$ holds the speed at $90 \mathrm{~m} / \mathrm{s}$ without re-trimming at SSL (air density $=1.22$ $\mathrm{kg} / \mathrm{m}^{3}$ ). To fly at $3000 \mathrm{~m}$ altitude (air density $=0.91 \mathrm{~kg} / \mathrm{m}^{3}$ ) and $120 \mathrm{~m} / \mathrm{s}$ TAS without re-trimming, the aircraft needs
(A) $1.95 \mathrm{~N}$ upward force.
(B) $1.95 \mathrm{~N}$ downward force.
(C) $1.85 \mathrm{~N}$ upward force.
(D) $1.75 \mathrm{~N}$ downward force.