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Electrified wingsuit from BMW reaches 186MPH on first flight

robbreport.com

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Re: Electrified wingsuit from BMW reaches 186MPH on first flight

#21

Post by nikda »

CrazyCatDog wrote: post #16
Robotbeat wrote: post #12

Lithium-based batteries (and associated tech) are to the 21st century what the internal combustion engine was to the 20th century and what the steam engine was to the 19th century. There’s a ~90% chance you’re using a device powered by a lithium chemistry battery to read this right now (laptop or tablet or phone). The smartphone alone (enabled by lithium based batteries) has transformed the world. Lithium-based batte…

Lithium ion cannot output enough (low C) to make this feasible (yet). Much more likely using Li-Po cells, which are far more adept at emptying themselves at high load—but thermal runaway (eg insanely hot fires) is all too real with Li-Po, though less so today than say 6 years ago!

From Wikipedia: A lithium polymer battery, or more correctly lithium-ion polymer battery (abbreviated as LiPo, LIP, Li-poly, lithium-poly and others), is a rechargeable battery of lithium-ion technology using a polymer electrolyte instead of a liquid electrolyte.

Re: Electrified wingsuit from BMW reaches 186MPH on first flight

#22

Post by patentatt »

CrazyCatDog wrote: post #14

An electric ducted fan (EDF) is highly inefficient, had they put similar wattage through a gearbox to say a folding prop, efficiency may have doubled (albeit an admittedly more onerous form factor). This is just the beginning of electric assist single passenger flight! Reference: plenty of experience pushing 8KW+ through 2KG RC gliders (F5B) and far slower EDF models.

Bit of an aside, but are you saying you are flying an EDF glider?

Re: Electrified wingsuit from BMW reaches 186MPH on first flight

#26

Post by CrazyCatDog »

patentatt wrote: post #22
CrazyCatDog wrote: post #14

An electric ducted fan (EDF) is highly inefficient, had they put similar wattage through a gearbox to say a folding prop, efficiency may have doubled (albeit an admittedly more onerous form factor). This is just the beginning of electric assist single passenger flight! Reference: plenty of experience pushing 8KW+ through 2KG RC gliders (F5B) and far slower EDF models.

Bit of an aside, but are you saying you are flying an EDF glider?

Haven’t bothered :) Only “toy” EDF models, performance from an 8KW system revving at 60K rpm at 10S (10 lipo cells in series) swinging a 19” folding prop is on par with a mini turbine in terms of performance (0-> 180mph+ in under 2 seconds). Granted this is for 2 meter gliders, but I would expect similar efficiencies in larger scale applications (the bmw EDF is not that much larger than RC).

Re: Electrified wingsuit from BMW reaches 186MPH on first flight

#27

Post by Retric »

freeflight wrote: post #10
Retric wrote: post #3

Amusingly that’s actually much slower than the world record for unpowered wingsuit horizontal speed of 246.6 mph.

Tho that was not what was tested, this is about having additional thrust to regain altitude and fly longer distances: > “I found the idea of being able to jump from my local mountain wearing the wingsuit and land in my garden fascinating.”

Sure, I just find it funny how in most cases 180MPH is fast, but that’s about the minimum speed for horizontal wingsuit flight. You really can strap a get engine to a brick and get it to fly, but you can’t stick a jet engine to a brick and get it to fly slowly.

EX: F-15 landed safely with just one wing. A little cough propaganda, but still interesting: https://www.youtube.com/watch?v=M359poNjvVA.

Re: Electrified wingsuit from BMW reaches 186MPH on first flight

#28

Post by Robotbeat »

CrazyCatDog wrote: post #16
Robotbeat wrote: post #12

Lithium-based batteries (and associated tech) are to the 21st century what the internal combustion engine was to the 20th century and what the steam engine was to the 19th century. There’s a ~90% chance you’re using a device powered by a lithium chemistry battery to read this right now (laptop or tablet or phone). The smartphone alone (enabled by lithium based batteries) has transformed the world. Lithium-based batte…

Lithium ion cannot output enough (low C) to make this feasible (yet). Much more likely using Li-Po cells, which are far more adept at emptying themselves at high load—but thermal runaway (eg insanely hot fires) is all too real with Li-Po, though less so today than say 6 years ago!

You’d be surprised. There are some high-C lithium ion cells, but they’re not as easily available as LiPo. If you need to dump your power over 4-10 minutes or longer at peak power, there are lithium ion cells available. Less than 4 minutes, LiPo is still better for now.

Re: Electrified wingsuit from BMW reaches 186MPH on first flight

#29

Post by kzrdude »

demarq wrote: post #24

Something seems suspect here. There is just no way that small unit could generate near enough thrust to make a real difference. I think we need to look deeper into this claim

He's starting from a plane, so his flight is mostly powered by the fall and the updraft of the wingsuit. Additionally, it may look as if he's soaring when just gliding with a small change in perspective
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