Pipistrel VELIS Electro, Pilot Operating Handbook

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VELIS Electro
Pilot's Operating Handbook
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SECTION 5
PERFORMANCE DATA
APPROVED
5.12 MISSION PLANNING - EXAMPLES
Following examples show typical mission profiles and scenarios. Parameters
for calculation are taken from tables in current Section 5 - Performance Data.
A ) POINT OF NO RETURN ( PNR ) - CALCULATION EXAMPLE:
When flying the VELIS Electro outside the circuit pattern, it is important to
estimate when the remaining energy is su ffi cient for a safe return to home
base. The PNR (Point of No Return) in flight is when there is just su ffi cient
SOC to return to base (and arrive there with 30%). This PNR is calculated for
flights from point A to point A (A-A Flight). Most VELIS Electro flights are A-A.
NO WIND CONDITION - CALCULATION EXAMPLE
When flying in no wind conditions along a straight track, calculating PNR is
not particularly di ffi cult. There is enough SOC available to take o ff and fly
toward the destination knowing, that as long as the flight does not proceed
beyond the halfway point, it should be possible to make it back to home
airfield safely.
If the take o
ff is with 100% SOC, landing must be planned at minimum 30%
SOC. Therefore total usable SOC is 70%. If (example) 10% of the SOC is
used for the climb to cruise altitude, the remaining 60% is available for the
cruise. Half of SOC available for cruising is 30%. So the turning back to the
initial cruise point occurs after using 10% SOC for climbing and 30% of SOC
available for cruise: PNR results at 60% of SOC (100%-10%-30% = 60%). The
example assumes that cruise initial/final points are in proximity of the airport.
"PNR REFERENCE TABLES" provided in this section can be used for easy
calculation of PNR.
WINDY CONDITION - CALCULATION EXAMPLE
Cruise speed 85 kts (example), and outbound tailwind of 15 kts (from GPS
ground speed reading). The di ff erence between the IAS and TAS at VELIS
Electro altitudes are negligible and is possible to consider IAS = TAS.
Therefore:
GS outbound: 85 kts + 15 kts (tailwind) = 100 kts
GS inbound: 85 kts - 15 kts (headwind) = 70 kts
The %SOC to PNR is calculated with the PNR equation: