Wk4 Fall 2020

This week we split into two groups. One group went to Martell with Dr. Hupy and Zach, while the other was at PWA with me and William. At PWA I took my group and we did weighted flights with the DJI Phantom 4 Pro. This flight was to test; first the lifting capabilities of the aircraft, second the was to test flight stability, and lastly we checked the top speed of the aircraft at 250ft AGL. 

DJI Phantom 4

The first test was unweighted. This was set as the base line for the flight. The aircrafts take off characteristics were noted as level take off. Once in flight at 25ft, the full stick deflection was preformed to test flight stability. The aircraft has stable and steep deflection compared to the M600, M210, and Mavic Pro 2. But it was able to keep its position in space. Finally, a 1-mile speed test was flown. The top speed was 43.8 mph for one mile. This was the base line and how everything else was to be compared to.

Next a 3D printed camera mount was fixed to between the legs. Two half pound ingots were fastened to the mount and performance was noted. The take off had a slight fall backwards but the vehicle was able to take off. It easily claimed to 25ft and the full stick deflection was done. The aircraft slipped very lightly in place but was able to keep stable. Then the vehicle was climbed to 250ft and was flown to top speed. A flight speed of 42 mph was achieved. It is believed that a one-pound weight could easily been flown. 

Phantom 4 Rear Mount

The last flight turned into two parts. Originally it was supposed to be flown with a three-pound payload. During take off the controller gave a max RPM warning on the motors. The vehicle achieved a max height of 1 foot then immediately began sinking back to the ground. So the test was changed to a two pound load. The aircraft had a higher than normal take off RPM but no warning was given. After staying at 2 ft AGL for one minute, the aircraft was flown into position for the stability test. With full stick deflection, there was lots of slipping and instability with rapid direction changes. At 25ft the aircraft was left to maintain its location but after a minute the vehicle began to sink and gave no indication on the controller or otherwise. With additional input it would regain stability. The speed test was done and a top speed was held at 40 mph with no altitude loss. Below is a screen shot from the flight recording.

Photo taken from Video Recording

During to post flight debrief, it was noted the 3lb pay load was excessive and beyond the aircrafts limits. It was concluded that a max external payload was likely 2.5lbs. No data exists for the Phantom 4 Pro so this was all experimental. The flights were successful and the data needed was obtained. The next step is to load the aircraft for drop tests.