Mars Helicopter

[A64Pilot]

Maybe a heat balloon would work better, using Martian atmosphere, it’s cold as the devil there and they work off of heat differential of course, but the source of heat would be an issue.

[Hank]

1 hour ago, N201MKTurbo said:

The balloon would take a huge amount of hydrogen and the envelope would need to be huge. Recall the high altitude balloon rides a few years ago. They had a hard time getting much above 100000 Ft which is the density altitude at the surface of Mars, so they would be starting near the limits of what a balloon can do. Without doing the math, I would imagine the balloon would need to be 50 feet in diameter.

There is a place called World View just south of Raytheon Missile Systems in Tucson. They fly high altitude balloons. When they are filling a balloon 2-4 tank trucks of hydrogen show up.

The Martian equipment payload is much smaller, so less lift would be needed. Then Martian gravity is 3/8g?, so less lift would be needed. Both make for a smaller balloon, so less lift would be needed. So a much smaller balloon would lift the smaller payload, requiring much less H₂. How much less, I dunno--too many variables to make even a semi-educated approximation . . . .

[EricJ]

There are minor downsides to balloons compared to helicopters, like maneuverability, navigability, can land and take off again multiple times without too much hassle, can accurately pick a suitable landing spot for survey/experimentation/etc.

I suspect being able to lift something won't always be the only requirement.

 

[A64Pilot]

wind speed is I believe horrendous on Mars, so balloon would have to be stowed, or be single mission

[Gagarin]

High-altitude balloons are crewed or uncrewed balloons, usually filled with helium or hydrogen, that are released into the stratosphere, generally attaining between 18 and 37 km (11 and 23 mi; 59,000 and 121,000 ft) above sea level. In 2002, a balloon named BU60-1 reached a record altitude of 53.0 km (32.9 mi; 173,900 ft).^[1]

And the above is on Earth. Best helicopter helicopter will do 30,000 ft.

High altitude balloons are commonly used for weather observation.

Edited March 29, 2021 by Gagarin

[A64Pilot]

We can’t compare this thing to a terrestrial helicopter. especially a “real” helicopter.

‘The fact that they can make a helicopter fly is impressive, but not nearly as impressive as the fact that it’s Solar powered, there can’t be much insolation on Mars, and does it fly with the panel that charges it? If so then that is really impressive.

Edited March 29, 2021 by A64Pilot

[0TreeLemur]

On 3/29/2021 at 5:15 PM, A64Pilot said:

We can’t compare this thing to a terrestrial helicopter. especially a “real” helicopter.

‘The fact that they can make a helicopter fly is impressive, but not nearly as impressive as the fact that it’s Solar powered, there can’t be much insolation on Mars, and does it fly with the panel that charges it? If so then that is really impressive.

So the endurance figure the design report gives at the battery end of life is approx. 45 seconds on a single charge.   New batteries might propel the thing for more than 90 seconds.   Not sure about charging time, depends on random factors like panel orientation and atmospheric opacity (dust).  Solar constant at Mars is about 580 W/m², top of atmosphere.

The crazy thing is- not only do the batteries pull duty to power flight and guidance/radios but they also power heaters at night to keep the cells from getting too cold, which will kill them.  One good feature is that they can spin up the rotors to dust off the solar panel.

Should have first flight this week!

[cliffy]

On 3/29/2021 at 9:28 AM, N201MKTurbo said:

There is a place called World View just south of Raytheon Missile Systems in Tucson. They fly high altitude balloons. When they are filling a balloon 2-4 tank trucks of hydrogen show up.

They launch their balloons at KPGA

[N201MKTurbo]

18 minutes ago, cliffy said:

They launch their balloons at KPGA

Ever since they tried to blow up RMS!

They used to launch them in Tucson. 
 

Everybody at Raytheon thought the building next door blew up. After all they do make bombs there.
 

 

Edited April 5, 2021 by N201MKTurbo

[cliffy]

It just went "BOOM"   :-)

[ArtVandelay]

wind speed is I believe horrendous on Mars, so balloon would have to be stowed, or be single mission

But the atmosphere is so thin, the rpms of the helicopter blades must be very high.

[thinwing]

On 3/28/2021 at 4:49 AM, N201MKTurbo said:

You would need to carry the balloon envelope and the supply of hydrogen all the way to mars, that’s a lot of weight in itself. You would also need the mechanism for filling it and deploying it. This sounds like a lot to haul around. 

it wouldnt work....in order to "float"the bag would have to be big enough to displace its own weight...co2 partial pressure as already stated is so low,the bag containg even the lightest gas element (hydrogen) would have to be the size of football stadium.The fabric containing the gas is proportionally too heavy.100,000 ft (partial prssure at mars surface)is about at the maximum practcle alitude a gas balloon could fly.

[jaylw314]

14 hours ago, ArtVandelay said:

But the atmosphere is so thin, the rpms of the helicopter blades must be very high.

They are, Ingenuity's rotor's are about 24" radius and spin at 2600 RPM or something like that.  That kind of makes my head hurt thinking about it, my quadcopters would do almost the same RPM but are only 6" radius!