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#126 2021-09-17 20:07:51

SpaceNut
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Re: Ingenuity, Scouting Mars by Helicopter

I think the issue is the wireless communications can not get a good link back to the rover for further commands accurately for the rovers reciever transmitter antenna system..

No dates are given for the scaling of design work for heavier and larger helicopters but I hope they are sooner not later.
https://rotorcraft.arc.nasa.gov/Publica … _final.pdf
An Advanced Mars Helicopter Design

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#127 2021-09-17 20:24:17

tahanson43206
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Re: Ingenuity, Scouting Mars by Helicopter

For SpaceNut re #126

The report indicated that the density of the air on Mars is changing.  This is (according to the article) not unexpected.

Ingenuity was not expected to last this long.    It has almost no air to work with in the first place, and now it has less.

Radio communication is not a factor in the situation. 

I tried to include the crucial information in the quote, because I know that forum members do not have time to visit every link that gets posted. 

In this case, since my quote somehow caused you to think radio communication had something to do with the problem, it would appear necessary to take the time to read the original article.

(th)

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#128 2021-09-17 20:31:20

SpaceNut
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Re: Ingenuity, Scouting Mars by Helicopter

Density changes with altitude as they are going up the hill...it also changes from night to day and from summer to winter...

I am also wondering if mars dust is also playing into this as the build up on the surfaces would add mass for its current flights that its making causing it to need more energy for lift and if the rotors are also getting dust into the sleeve bearings then the tip speeds are also slowing...

edit
I double check the weather topic to see what the barometer was doing and its going down
here is the comparison of the rover sights
24729_PIA23518-Mars-landing-sites-web.jpg

So is the atmospher shape to depth shifting as we go from winter to summer or vis versa...as there is a shift of 35 to 50 kpa in pressure since the periods of the comparisons were made in the weather topic.

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#129 2021-09-18 09:50:59

SpaceNut
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Re: Ingenuity, Scouting Mars by Helicopter

https://mars.nasa.gov/technology/helico … nd-harder/

When we designed and tested Ingenuity on Earth, we expected Ingenuity’s five-flight mission to be completed within the first few months after Perseverance’s landing in February 2021. We therefore prepared for flights at atmospheric densities between 0.0145 and 0.0185 kg/m3, which is equivalent to 1.2-1.5% of Earth’s atmospheric density at sea level. With Ingenuity in its sixth month of operation, however, we have entered a season where the densities in Jezero Crater are dropping to even lower levels. In the coming months we may see densities as low as 0.012 kg/m3 (1.0% of Earth’s density) during the afternoon hours that are preferable for flight.

The difference may seem small, but it has a significant impact on Ingenuity’s ability to fly. At our lower design limit for atmospheric density (0.0145 kg/m3), we know that Ingenuity has a thrust margin of at least 30%. Thrust margin refers to the excess thrust that Ingenuity can produce above and beyond what is required to hover. That additional thrust is needed on takeoffs and climbs, during maneuvers, and also when tracking terrain with varying height. But if the atmospheric density were to drop to 0.012 kg/m3 in the coming months, our helicopter’s thrust margin could drop to as low as 8%, which means that Ingenuity would be operating close to aerodynamic stall (a condition where further increases in the blade’s angle of attack does not produce more lift, only more drag).

We will begin by performing a high-speed spin of the rotor without leaving the ground, reaching a peak rotor speed of 2,800 rpm (more than a 10% increase relative to our prior Mars experience of 2,537 rpm). If all goes well, we will follow this with a short test flight at a slightly lower rotor speed of 2,700 rpm.
A rotor speed of 2,800 rpm, in combination with wind and helicopter motion, could cause the tips of the rotor blades to encounter the air at nearly 0.8 Mach – that is, 80% of the speed of sound on Mars.

Flight elevaional change from starting on mars elevation to the last flight has gone up
PIA24690-web.jpg

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#130 2021-09-18 10:21:34

tahanson43206
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Re: Ingenuity, Scouting Mars by Helicopter

For SpaceNut re helicopter ...

In a light hearted moment of enthusiasm, you recently suggested a helicopter might be a useful addition to the Landing Site engineering probe design. 

The lander (per Drafts 1-6 by GW Johnson) is NOT designed to carry out ANY exploration of ANY kind beyond the two dedicated mission objectives:

1) drill 10 meters down for water
2) Pound the soil for many meters all around the lander, to characterize the regolith for a future lander

A helicopter would  consume mass and (as far as I can see) contribute nothing to the success of the primary mission.

However, you may well see a value to having a helicopter on the scene that I've missed, so here is your chance to elaborate on why such a vehicle should be included.

(th)

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#131 2021-09-18 10:25:54

SpaceNut
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Re: Ingenuity, Scouting Mars by Helicopter

Speed to map a safe course travel lane for the rover that needs to get to a site to drill since we are making the rover to be tiny and unless they carry solar panels to keep powered up the distance from the lander for recharge makes for a slow limited path by the rovers cameras being used to pick a course as the current rovers do now is very slow.

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#132 2021-09-18 19:05:48

tahanson43206
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Re: Ingenuity, Scouting Mars by Helicopter

For SpaceNut .... re #131

The rover is a pounder, not a drill.

The drill is fixed in position and does not need the helicopter.

The rover is a ground vehicle that moves in 1 meter steps to pound the soil, take observations, retrieve the pounder and move again.

There is no need for a helicopter for a landing pad engineering mission.

Edit: On second thought ... perhaps a helicopter ** would ** make sense, if it can be fitted into the mass allocation that GW Johnson appears to have in mind.

It occurred to me that a helicopter could scan the entire area of the landing pad quite rapidly, whereas the rover is going to move very slowly, a meter at a time, in order to visit every square meter of the landing pad at a given site.  Perhaps the helicopter could save the rover-pounder time by identifying rocks that are going to prevent a landing at that site.

The drill needs to complete it's work even if the landing site has to be scrubbed, because if there is water present, then another landing site can be used, and an overland expedition can visit the scrubbed site.

OK ... it's up to GW Johnson now to decide if he wants to try to add the complexity of a helicopter to what was intended to be a very simple mission to obtain just two kinds of data.

(th)

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#133 2021-09-29 20:03:06

SpaceNut
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Re: Ingenuity, Scouting Mars by Helicopter

The testing of the higher level of rpm for sustained flight has caused it to give an error so no flight for now until they figure it out.

NASA aborts flight Mars helicopter flight after 'anomaly' detected

AAOXKI9.img?h=480&w=799&m=6&q=60&o=f&l=f

This flight would have shown Ingenuity's ability to fly with 2,700 revolutions per minute, slightly more than the 2,537 rpms it has used previously

higher rpm require for the new lift value due to lessening air pressure.

INGENUITY FLIGHTS SO FAR
Flight one: April 19, 2021 with a vertical takeoff up to 9.8ft, stationary hover and a landing

Flight two: April 22, 2021 with a vertical takeoff up to 16ft, hover, then shift westward for 14ft before returning and landing

Flight three: April 25, 2021 with a vertical takeoff up to 16ft, hover, shift northwards for 328ft at an airspeed of 2 m/s before returning to land

Flight four: April 30, 2021 with a vertical takeoff up to 16ft, hover, shift southwards 873ft at 3.5m/s before returning to land

Flight five: May 7, 2021 with a vertical takeoff up to 33ft, hover, shift southwards 423ft at 3.5 m/s before landing at that new location

Flight six: May 22, 2021 with a vertical takeoff of 33ft, hover, shift southwest 492ft at 9mph, travel 49ft south, travel 164ft before returning to land

Flight seven: June 8, 2021 with a vertical takeoff of 33ft, hover, shift 348ft at 9mph, land at Airfield D

Flight eight: June 21, 2021 with a vertical takeoff, hover, shift southwest 520ft, land at Airfield E 438ft away from Perseverance

Flight nine: July 5, 2021 with a record length of 2,050ft southwest over a prospective research location at 16ft per second.

Flight 10: July 24, 2021 with a record height of 40 feet (12 meters) over Raised Ridges to Airfield G. Flight duration 165.4 seconds.   

Flight 11: August 5, 2021 by flying 1,250ft for 130 seconds in preparation for a series of reconnaissance missions for the Perseverance rover.

Flight 12: August 16, 2021 by flying 1,476ft for 169 seconds, climbing 32.8ft in the air, over the 'South Seitah' region of Mars.

Flight 13: September 5, 2021 by flying 690ft for 160.5 seconds, climbing 26ft over one particular ridgeline over the 'South Seitah' region of Mars.

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#134 2021-10-25 19:43:39

SpaceNut
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Re: Ingenuity, Scouting Mars by Helicopter

Time to get ready Mars helicopter Ingenuity approaches 14th flight

The Mars helicopter Ingenuity is ready for a short Martian flight as early as Saturday to test summer weather conditions that have arrived at its location on the Red Planet after two weeks of no communication because of blockage by the sun.

As the heat of summer grows the mars air is going to get thinner and will require even higher rpm's for the blades to create sufficient lift.

What is the lift formula or equation?

The lift formula or equation is CL ½ p V2 S.
CL is the coefficient of lift.  In general, this is the angle of attack on the rotor blade.  Until the stalling angle is reached, an increase in the CL will produce more lift.

½ p V2 This section of the formula is Dynamic Energy or Kinetic Energy.  Basically, dynamic/kinetic energy is derived from the movement of air.  The p is for pressure or air density.*  The greater the density (lower pressure altitude) the more lift produced.

V2 is for velocity or the rotor RPM with regards to helicopter flight.  As referenced by the squared component, velocity is a major factor in lift production.

CL=ρv2A2L

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#135 2021-11-09 20:06:35

SpaceNut
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Re: Ingenuity, Scouting Mars by Helicopter

The 15th flight  has happened and its returned basically back to near its starting point to support the rovers new direction of travel.

https://www.space.com/mars-helicopter-i … 5th-flight

https://mars.nasa.gov/technology/helico … n-journey/

The team lead Teddy Tzanetos of JPL laid out the flight plan in that post, stating that Ingenuity would cover 1,332 feet (406 meters) of horizontal distance, travel at 11.1 mph (17.9 kph) and fly about 39 feet (12 m) above the ground. The recent flight was also the second in which Ingenuity spun its rotors at 2,700 revolutions per minute  (RPM), compared to about 2,500 RPM on the first 13 flights. The increase was necessitated by a seasonal shift on Jezero's floor; it's summer there now, and the air is less dense

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#136 2021-11-23 18:23:46

SpaceNut
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Re: Ingenuity, Scouting Mars by Helicopter

Mars helicopter Ingenuity completed its 16th flight over the weekend, the space agency announced Monday.

wow 7 months on Mars

The NASA Jet Propulsion Laboratory said the helicopter captured color images of Mars' surface during the flight, which saw it travel 116 meters northeast for 109 seconds.

Now can we make it for human size?

update for flight 17

The 17th flight of NASA's Ingenuity Mars Helicopter on Dec. 5 pushed the total flight time past the 30-minute mark.

Along with accumulating 30 minutes and 48 seconds of flight time, the trailblazing helicopter has traveled over the surface a distance of 2.2 miles (3,592 meters), flying as high as 40 feet (12 meters) and as fast as 10 mph (5 meters per second).

https://mars.nasa.gov/technology/helicopter/

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#137 2021-12-21 21:22:24

SpaceNut
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Re: Ingenuity, Scouting Mars by Helicopter

The little helicopters name may be Ingenuity but maybe it should have been Timex or EverReady as it keeps going and going as  NASA's Mars helicopter Ingenuity notches 18th flight traveling 754 feet at 5.6 mph

Ingenuity's total flight time on Mars has exceeded 32 minutes.

The tiny helicopter was designed to fly only a few minutes over 30 days as a technology demonstration, but has passed eight months in operation.

NASA had lost radio contact -- except for very brief transmissions -- after Ingenuity's Flight 17 on Dec. 5. Hills between the helicopter and the Perseverance rover blocked the link.

But the Mars helicopter's team said in a press release that it was able to downlink more data Dec. 10.

NASA has said the helicopter is in excellent condition. Following the radio interruption, engineers altered the helicopter's communication link to operate in a safe mode during flight, meaning it won't relay as much data, but the signal is stronger.

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#138 2022-01-20 20:11:47

SpaceNut
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Re: Ingenuity, Scouting Mars by Helicopter

Ingenuity helicopter flight stalled for first time due to unusual Mars weather because of an unusually strong regional dust storm on Mars, according to NASA.

Now, the team anticipates that this flight will take place on Sunday, January 23.

As the seasons change, the air density goes through a cycle of ups and downs on Mars. Air density is one of two crucial factors when it comes to calculating favorable conditions for flight on Mars. Wind speed is the other factor.

Perseverance first spotted the approach of the January storm as dust lifted around the two robotic explorers in Jezero Crater.

From orbit, the Mars Reconnaissance Orbiter observed an expanding regional dust storm moving from the southern hemisphere to the northern hemisphere on Mars. From the orbiter's perspective, it appeared that the storm may be heading for the crater and the two robots within it.

After a dust storm reduced the sunlight that could reach its solar panels, the InSight lander, which is more than 2,000 miles (3,219 kilometers) to the east of Perseverance, entered safe mode on January 7.

Maybe the little helicopter should seek the safety of being under the rover for a bit to protect its solar panel.

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#139 2022-02-28 21:18:28

SpaceNut
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Re: Ingenuity, Scouting Mars by Helicopter

Seems I missed a few flights
Ingenuity helicopter aces 20th Mars flight

and was granted an extension, during which it's been serving as a scout for Perseverance and pushing the limits of Red Planet flight. And on Friday (Feb. 25), Ingenuity notched yet another milestone, this one of the round-number variety — its 20th Martian sortie.

"Flight 20 was a success! In its 130.3 seconds of flight, the #MarsHelicopter covered 391 meters [1,283 feet] at a speed of 4.4 meters per second [9.8 mph], bringing it closer to @NASAPersevere's landing location," NASA's Jet Propulsion Laboratory in Southern California, which manages the missions of both Ingenuity and Perseverance, said via Twitter on Saturday (Feb. 26).

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#140 2022-03-13 08:50:12

Mars_B4_Moon
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Re: Ingenuity, Scouting Mars by Helicopter

Ingenuity still “as good as new” after nearly a year on Mars

https://spacenews.com/ingenuity-still-a … r-on-mars/

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#141 2022-03-13 12:53:07

SpaceNut
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Re: Ingenuity, Scouting Mars by Helicopter

Wow number 21 when the little helicopter was to just di five flights.

NASA’s Jet Propulsion Laboratory announced March 11 that Ingenuity completed its 21st flight on the planet, traveling 370 meters during the 129-second flight. The helicopter has now traveled more than 4.6 kilometers since its first flight in April 2021.

The information Ingenuity has provided has created some modest time savings for Perseverance. “It’s certainly shaved several sols, maybe a week, off of the time frame of the rover by having this advanced information,”

The terrain is not optimal for a rover,” he said of the region. “These insights have been invaluable.”

That work will continue as Perseverance heads in the coming weeks to the remnants of a river delta. “The intent is to keep the helicopter out in front of the rover to provide advance information that would help in its exploration,” Golombek said. That includes scouting paths the rover could take into the delta and identifying rocks for the rover to study with its instrument suite.

So far its travel a greater distance in a shorter period of time.

Its also shown that clean solar panels to power some items will work.

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#142 2022-04-14 08:10:52

Mars_B4_Moon
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Re: Ingenuity, Scouting Mars by Helicopter

Mars helicopter Ingenuity aces record-breaking 25th flight

https://www.space.com/mars-helicopter-i … 5th-flight

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#143 2022-04-14 18:45:14

tahanson43206
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Re: Ingenuity, Scouting Mars by Helicopter

Here's another report on the record breaking flight!

Nod to Mars_B4_Moon for the scoop!

https://currently.att.yahoo.com/news/na … 28367.html

Nasa’s Mars helicopter completes record breaking flight
Jon Kelvey

Thu, April 14, 2022, 11:42 AM

The shadow of Ingenuity, Nasa’s Mars helicopter, can be seen to the lower left as the vehicle soars above the Martian landscape (Nasa)

Nasa’s Ingenuity helicopter just completed its 25th flight on the Red Planet, flying further and faster than ever before.

On April 8, the 1.8-kilogram, dual rotor helicopter lifted off the Martian surface to execute a flight plan prepared by the Ingenuity team at Nasa’s Jet Propulsion Laboratory, traveling 704 meters at about 5.5 meters-per-second to explore a dry river delta within the Jezero Crater.


The new record-setting flight is a far cry from Ingenuity’s first flight on 19 April 2021, when the helicopter merely hovered for 30 seconds. It’s also a significant improvement on Ingenuity’s previous best flight on 5 July 2201, which covered 625 meters of Martian ground.

Ingenuity first arrived on Mars on 18 February 2021 carried by Nasa’s Perseverance rover. After demonstrating the first-ever powered, controlled flight on another world — something scientists weren’t sure would work until it did — Ingenuity has served as an aerial scout for the rover as the two explore Jezero Crater. A site once believed to have held water, the crater could hold signs of past or present Martian life — if it exists or ever existed.

For the continually record-setting Ingenuity mission and its contributions to aerospace technology, the Ingenuity team was recently awarded the prestigious Collier Trophy, an award given annually to recognize American achievements in aerospace since 1911. Past recipients include Orville Wright (of the Wright Brothers) and the crew of Apollo 11.

Our goal is to create a safe and engaging place for users to connect over interests and passions. In order to improve our community experience, we are temporarily suspending article commenting

(th)

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#144 2022-04-14 20:02:44

SpaceNut
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Re: Ingenuity, Scouting Mars by Helicopter

from my post back in March for flight 21 to current means they are flying it each week. That is quite a bit of air time for something that they did not think would even work and a good reason to follow it up with other machines to do even greater exploration without a rover....

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#145 2022-05-08 05:32:33

Mars_B4_Moon
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Re: Ingenuity, Scouting Mars by Helicopter

NASA's Ingenuity in contact with Perseverance after communications dropout

https://www.marsdaily.com/reports/NASAs … t_999.html

Ingenuity became the first powered aircraft to operate on another world on April 19, 2021. Designed to perform up to five experimental test flights over a span of 30 Martian days (sols), or close to 31 Earth days, the rotorcraft has flown over 4.2 miles (6.9 kilometers) across 28 sorties and operated from the surface of the Red Planet for over a year.

Data downlinked indicates that the communications dropout on May 3, Sol 427 of the Perseverance rover's mission at Mars, was a result of the solar-powered helicopter entering a low-power state, potentially due to the seasonal increase in the amount of dust in the Martian atmosphere and lower temperatures as winter approaches. The dust diminishes the amount of sunlight hitting the solar array, reducing Ingenuity's ability to recharge its six lithium-ion batteries. When the battery pack's state of charge dropped below a lower limit, the helicopter's field-programmable gate array (FPGA) was powered down.

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#146 2022-05-08 19:25:47

SpaceNut
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Re: Ingenuity, Scouting Mars by Helicopter

This will mean less flights and more charging days.

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#147 2022-05-09 20:03:12

SpaceNut
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Re: Ingenuity, Scouting Mars by Helicopter

Ingenuity Mars Helicopter Went Silent, Leaving Anxious NASA Team in the Dark

The team behind the mission believes that Ingenuity had entered into a low-power state to conserve energy, and it did so in response to the charge of its six lithium-ion batteries dropping below a critical threshold. This was likely due to the approaching winter, when more dust appears in the Martian atmosphere and the temperatures get colder. The dust blocks the amount of sunlight that reaches the helicopter’s solar array, which charges its batteries.

Another example of dust and winter combining to allow for batteries to fail....with admission

Ingenuity wasn’t exactly built to withstand the harsh Martian winter nights, as the rotorcraft was designed to last only 30 sols on Mars.  “We have always known that Martian winter and dust storm season would present new challenges for Ingenuity, specifically colder sols, an increase in atmospheric dust, and more frequent dust storms,” Teddy Tzanetos, Ingenuity team lead at JPL, said in a statement.

a plan to help the tiny helicopter survive the looming winter. The newly issued commands “lower the point at which the helicopter energizes its heaters from when the battery falls below 5 degrees Fahrenheit (minus 15 degrees Celsius) to minus 40 degrees Fahrenheit (minus 40 degrees Celsius),” according to NASA, which added that the “helicopter then shuts down quickly, rather than consuming the battery charge with the heaters.” This should allow Ingenuity to accumulate battery charge during the day, which it can then use to survive the bitterly cold nights.

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#148 2022-05-29 16:45:01

SpaceNut
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Re: Ingenuity, Scouting Mars by Helicopter

It has been nothing short of fantastic for something that was not really done with a whole heart in its minimal package size but its come through well above expectations.
NASA's Ingenuity Helicopter Captured Video Of Its Record Flight Across Mars

The vehicle was originally designed to perform just five flights, but it has been so successful that it has kept flying and is preparing for its 29th flight, according to the space agency. However, there are problems ahead for the helicopter. As it has been operating for so long, it now must operate during the dusty season on Mars. As seasons on the planet change, the amount of dust in the atmosphere changes, too. Now, in the Jezero crater where the helicopter is, the amount of dust is increasing. This causes problems for Ingenuity as dust can cover its solar panels, making it harder to charge its batteries (via NASA). More dust in the atmosphere also means less sunlight can get through to the panels, making the problem even worse.

sounds like while we want solar in the end its only going to be as good as how clean the panels are....

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#149 2022-06-04 15:04:14

Mars_B4_Moon
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Re: Ingenuity, Scouting Mars by Helicopter

Perseverance Has a Pet Rock!
https://www.marsdaily.com/reports/Perse … !_999.html
This is not the first time a rock has hitched a ride on a Mars rover mission. Some 18 years ago, a "potato-sized" rock found its way into the Spirit rover's rear right wheel, and had to be dislodged. On the Curiosity rover, the front right wheel has periodically picked up its own traveling companion.

Data collected by Ingenuity is supporting planning of a future helicopter design by engineers at JPL, NASA's Ames Research Center and AeroVironment. The Mars Science Helicopter, a proposed successor to Ingenuity, would be a hexacopter, or six-rotor helicopter, with a mass of about 30 kg (66 lb) compared to 1.8 kg (4.0 lb) of Ingenuity. Mars Science Helicopter could carry as much as 5 kg (11 lb) of science payloads and fly up to 10 km (6.2 mi) per flight.
https://spacenews.com/nasa-studying-lar … licopters/

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#150 2022-06-04 21:13:53

SpaceNut
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Re: Ingenuity, Scouting Mars by Helicopter

I would chip in the extra money just to send more helicopters rather than the very slow rovers.

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