The run lasted 4 minutes 13 seconds. Ambient conditions were 19.7°C (67°F), 57.6% relative humidity and 101.0 kPa (29.8 inHg) barometric pressure.
We publish the whole sheet, not just the headline number. Thrust and fuel burn only mean something next to the conditions they were measured in, and a datasheet claim is worth less to a buyer than a record with a serial number on it.
01
Test conditions
The test was run static at sea level, with ambient temperature, humidity and barometric pressure logged before the engine started. At 101.0 kPa the pressure sits within 0.4 kPa of standard sea level, and 19.7°C is close to the ISA reference temperature. Results taken in this window can be compared with published figures without correction.
They do not transfer directly to altitude, hot-day operation or an installed airframe. Intake losses, exhaust geometry and bay cooling all move thrust and exhaust temperature, which is why the conditions are stated first rather than buried at the end.
02
Results
| Check | Factory requirement | Result | Margin |
|---|---|---|---|
| Start time | ≤ 45 s | 37.4 s | 7.6 s under |
| Maximum speed | ≥ 91,500 rpm | 91,500 rpm | at the limit |
| Maximum thrust | ≥ 40 kgf (88.2 lbf) | 43.14 kgf (95.1 lbf) | +7.9% |
| Specific fuel consumption | ≤ 1.55 kg/(kgf·h) | 1.48 kg/(kgf·h) | −4.5% |
| Maximum exhaust gas temperature | ≤ 870°C (1,598°F) | 842°C (1,548°F) | 28°C under |
| Maximum steady-state vibration | ≤ 15g | 6.1g | 41% of limit |
Each row carries a requirement, a measured value and a pass-or-fail conclusion recorded against serial 0045. The six items cover the variables that decide whether a turbojet is usable in service: how quickly it starts, how fast it turns, how much thrust it makes, what it costs in fuel, how hot it runs and how much it vibrates.
03
What the margins mean
Thrust cleared the requirement by 3.14 kgf, about 7.9%. The engine produced that figure at its rated maximum speed of 91,500 rpm, which met the specified floor exactly. The thrust margin came from the flow path at rated speed, not from running the engine beyond it.
Specific fuel consumption of 1.48 against a 1.55 limit is a 4.5% margin. In an airframe that difference converts into endurance or payload at a fixed fuel load, and it is the number that most directly sets mission radius.
Exhaust gas temperature of 842°C leaves 28°C below the 870°C limit. Vibration of 6.1g is 41% of the 15g limit. Both margins act on service life rather than on the day's performance: lower exhaust temperature slows hot-section wear, and lower vibration reduces fatigue load on the bearings and rotor assembly. Actual TBO is set per model and confirmed in the quotation.
Start time of 37.4 seconds, 7.6 seconds inside the 45-second limit, affects sortie rate. On a target drone or a high-speed UAV the start sequence sits between recovery and the next launch, and One-Key Start exists to keep that interval short.
04
What this test does not establish
An acceptance test answers a narrow question: does this unit meet its factory limits at sea-level static conditions. It does not cover altitude performance, hot-day derating, transient response, foreign object ingestion or endurance. It covers one engine, not a production sample.
Installation changes the numbers. Ducting, exhaust configuration and cooling all shift thrust and exhaust temperature, so we supply the engine and ECU as a matched set and support the first run rather than shipping a bare unit.
A buyer evaluating a 40 kgf-class engine should treat this sheet as the starting point for airframe validation, not as a substitute for it.
05
Fit and next step
The WP40 sits in the 40 kgf class, within the 20–160 kgf range we build for target drones, high-speed UAVs and fixed-wing airframes. Selection depends on all-up weight, wing loading, field elevation and mission profile, not on thrust alone. Send the target thrust, quantity and delivery region, and the reply names a model with its limits, accessory list and current lead time, within one business day.