So a relatively new article came out about this aircraft, previously discussed in another thread but didn't go much of anywhere without details
But they've now given us enough for us to check their math
https://www.aerosociety.com/news/bright-sparks-the-quest-for-electric-speed/
The basics:
GW: 926lbs/420kg (record attempt, regular 450kg)
Battery Weight: 265lbs/120kg
Hp:264hp/200kW (for 60sec, continuous is half that)
Performance (projected)
Speed: >250mph
Climb: 9,000 fpm
Endurance:
Record: 3.75 min with 20% reserve
Airshow: 10 min with 20% reserve
Now the Math:
The battery specs suggest, assuming max power run continuously for 4.5 minutes and 85% battery to motor efficiency
-145Wh/kg
-11.33 C
Which per (1), isn’t crazy to expect from a Lithium Manganese Oxide battery
Surprisingly, given a low energy density, low 10 L/D and prop efficiency 87% still achieves a range of 69 miles (2)
Is it practical? No. Could it replace several impractical aerobatic/racing ICE powered aircraft? I don’t see a reason why it can’t. And no P-factor would be fun in a high powered aircraft.
As usual, might have messed up somewhere, so please check
Sources
1)http://batteryuniversity.com/learn/article/bu_216_summary_table_of_lithium_based_batteries
2)And for those curious about the electric range equation
R(meters)=(Wh/kg*3600)*((powerplant efficiency)*(propeller efficiency))*(1/g)*(L/D)*(Battery weight/Gross weight)
From this at 51:10: https://www.youtube.com/watch?v=-yo820YZWqU&list=PL98EozRZbPbECY5dnWyZVrM4aj4qf7-Pz&index=32
3)And their homepage
http://www.electro-flight.com/electroflight-p1e (though seems somewhat out of date)
But they've now given us enough for us to check their math
https://www.aerosociety.com/news/bright-sparks-the-quest-for-electric-speed/
The basics:
GW: 926lbs/420kg (record attempt, regular 450kg)
Battery Weight: 265lbs/120kg
Hp:264hp/200kW (for 60sec, continuous is half that)
Performance (projected)
Speed: >250mph
Climb: 9,000 fpm
Endurance:
Record: 3.75 min with 20% reserve
Airshow: 10 min with 20% reserve
Now the Math:
The battery specs suggest, assuming max power run continuously for 4.5 minutes and 85% battery to motor efficiency
-145Wh/kg
-11.33 C
Which per (1), isn’t crazy to expect from a Lithium Manganese Oxide battery
Surprisingly, given a low energy density, low 10 L/D and prop efficiency 87% still achieves a range of 69 miles (2)
Is it practical? No. Could it replace several impractical aerobatic/racing ICE powered aircraft? I don’t see a reason why it can’t. And no P-factor would be fun in a high powered aircraft.
As usual, might have messed up somewhere, so please check
Sources
1)http://batteryuniversity.com/learn/article/bu_216_summary_table_of_lithium_based_batteries
2)And for those curious about the electric range equation
R(meters)=(Wh/kg*3600)*((powerplant efficiency)*(propeller efficiency))*(1/g)*(L/D)*(Battery weight/Gross weight)
From this at 51:10: https://www.youtube.com/watch?v=-yo820YZWqU&list=PL98EozRZbPbECY5dnWyZVrM4aj4qf7-Pz&index=32
3)And their homepage
http://www.electro-flight.com/electroflight-p1e (though seems somewhat out of date)
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