--- /dev/null
+# Test 2020-4 #
+
+3 grain 54mm Purple Pig motor with a Terry Lee dipped igniter in 3-inch test
+mule flown on 17 October 2020 at the first-ever Tripoli Southern Colorado
+launch at Hudson Ranch. In fact, this was the first-ever research flight
+flown at this location!
+
+Used 3-grain 54mm Kosdon case, Loki-style nozzle with an 0.390" throat,
+forward closure had a 1600psi pressure sensor and EasyMotor protototype
+mounted with an A23 alkaline battery, and shooter wire as a "twist and tape"
+power switch.
+
+The motor used three loose grains with 0.625" cores, thin o-rings as spacers,
+and a greased phenolic liner.
+
+[Burnsim](2020-test-4-burnsim.pdf) called this a 31% J-355, 838 Ns with
+about 2.36 sec burn time, and max pressure on a relatively flat burn of
+559.3s psi.
+
+## Results ##
+
+Perfect flight, no damage, easy recovery.
+
+This was the first flight during which we successfully captured in-flight
+chamber pressure data with an EasyMotor prototype board. A quick look at
+the data shows about 540 psi maximum, which is pretty close to the Burnsim
+prediction! Some software work remains to convert the data capture into
+actual motor performance data. The EasyMotor data is logged in file
+2020-10-17-serial-7085-flight-0007.eeprom
+
+The airframe's launch mass was about 4420 grams. The TeleMega on board
+reported 9.54 G max and 6.29 G average acceleration to a max speed of
+Mach 0.5 and a GPS apogee of 4669 feet. The TeleMega data is logged in file
+2020-10-17-serial-6667-flight-0003.eeprom
+
* [2020 batch 01](2020.08.31.html) - 31 August 2020 - 8 75mm KNSB grains
* [2020 test 01](2020-test-1.html) - 7 September 2020 - 8-grain 75mm KNSB at Airfest
+* [2020 test 02](2020-test-2.html) - 10 October 2020 - 4-grain 54mm Everclear at Kloudbuster October Fun Fly
+* [2020 test 03](2020-test-3.html) - 11 October 2020 - 4-grain 54mm Purple Pig at Kloudbuster October Fun Fly
+* [2020 test 04](2020-test-4.html) - 17 October 2020 - 3-grain 54mm Purple Pig at Tripoli Southern Colorado's first-ever launch!
### 2019 ###