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where the overall aircraft eciency during hover is η0,h = ηF,h · ηD,h · ηP E,h ·
ηM,h · ηB,h ≈ 59% and Pboard = 8kW through the whole flight. Substituting
into equation (46) gives
Ph = 2,570kW. (47)
It is an interesting academic question to calculate maximum hover time which
the power in Equation (46) and the total battery energy in Equation (1) would
allow.
tmax
h = Es ·(1 − SOCmin)
Ph
= 384s. (48)
It should, however, be noted that this hover time would in practice be impossible
because it would lead to overheating of the battery packs.
4.3.2. Cruise power
The cruise power Pcr is calculated with Equation (8) where once again Pboard
is added for the additional power consumption of air conditioning and avionics
during cruise flight as
Pcr =
P
i Di,cr · vcr
ηP,cr · ηD,cr · ηF,cr · ηP E,cr · ηM,cr · ηB,cr
+ Pboard.(49)
The aircraft’s cruise eciency is η0,cr = ηP,cr ·ηD,cr ·ηF,cr ·ηP E,cr ·ηM,cr ·ηB,cr ≈
65%. Substituting into Equation (49) gives
Pcr = 224kW. (50)
4.3.3. Transition power
The transition power Ptr is calculated with Equation (9)
Ptr,avg = (Ph + Ptr,eff )
2 + Pboard.(51)
where Ptr,eff = P h/10. Substituting into Equation (51) gives
Ptr,avg = 1,421kW. (52)
4.3.4. Climbing power
The climb power Pcl is calculated from Equation (10) as
Pcl = (P
i Di,cl + MT OM · g · sin(Φ)) · vcl
ηP,cl · ηD,cl · ηF,cl · ηP E,cl · ηM,cl · ηB,cl
+ Pboard.(53)
During climb, we set the climb angle to Φ = 5◦. This means that the thrust
of the aircraft has to overcome both the aircraft’s drag and a component of its
weight. This results in the power in climb being around twice the power in
cruise. As discussed earlier, during climb the altitude increases to 3000m and
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