Server down – repairing disk drive

After more than two years 24/7 the volume on my server degraded. One of the three hard disks crashed. Luckily there is some redundancy using Synology Hybrid Raid, and I am now trying to repair the volume. 5 TB of data at risk …

Once successful, will check the defect disk. Still should be under the 3-years warranty from WD.

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Project XE180 – Miniquad FPV

After I just completed my first own-built quad-copter, here a few details to share about this project. Having the DJI Phantom 2 V3 for aerial photography and a ready built 250 Storm racing drone, I was looking for a FPV mini-copter to fly indoor and outdoor, using brush-less motors and a robust carbon frame. My choice was XELITES ‘s  XE180, a 180 frame (motor to motor distance 180 mm).

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How fast can a quadcopter fly?

Introduction

Racing drones are becoming more and more popular, and it would not only be interesting to know, how fast they can really go, but also which parameters have a major impact on their maximum speed. When I searched in the net, I couldn’t find clear answers and had to work out something by myself; so here is my model. To be clear, my intention is not to get absolute precise numbers, but more to understand the physics behind, and to have a tool to get realistic estimates and comparisons of flight parameters for different quadcopter models. If you are not interested in the details, just scroll down to the end of the page, where I show the final formulas and some calculated examples.

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