NASA PLANS TO FLY A HELICOPTER OVER MARS

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Posted on 6/1/2018.

       When we heard that NASA wants to send a helicopter to Mars in 2020, the first thought was that unless (as we allege) NASA is ready to admit that they have misled the public about the real air pressure, this is an ill-conceived idea. However, as the video clip below shows, JPL claims to have test flown the tethered helicopter in 25-foot space simulator in Pasadena. Before delving into the science involved, let's take a look at a Torah Codes matrix in the issue. On Figure 1 the axis term is MARS HELICOPTER. There are two synonyms for TO LAUNCH at the same absolute skip. The Year 5080 on the Hebrew calendar, which includes 2020 is at skip +2. FEASIBLE is at one skip less than MARS HELICOPTER, but it shares a letter mem with it. In MARS HELICOPTER the word for Mars is a 3-letter transliteration of the English, but the Matrix also includes a 5-letter Hebrew word for MARS. The smaller (36-letter, grey background) matrix with MARS HELICOPTER, FEASIBLE, and TO LAUNCH is more significant than the full matrix. It was found against odds of about 12,881 to 1 and it addressed the main question - is such a helicopter feasible (in what is supposed to be an atmosphere with a density less than 1% of that found on Earth)?

Figutre 1 above - We consider two matrices with a 3-letter transliteration of MARS followed by HELICOPTER as the axis term. The first matrix (with a grey background) is only 36-letters in area. It has the a-priori terms FEASIBLE and TO LAUNCH in it. The second (full, 770-letter matrix) adds a second word for TO LAUNCH, a Hebrew word for MARS and the Hebrew Year of the expected launch (5080/2020). The spreadsheet below shows that the first (smaller) matrix is the more significant of the two.

Mars Helicopter
JPL Figure 1A: The Mars Helicopter, a small, autonomous rotorcraft, will travel with NASA's Mars 2020 rover, currently scheduled to launch in July 2020, to demonstrate the viability and potential of heavier-than-air vehicles on the Red Planet. Image credit: NASA/JPL-Caltech
› Larger view.

       The problem with their Figure 1A is that it only shows three blades with no obvious way to prevent torque, however the movie clip that follows in the JPL article shows two rotors (four blades) - one rotating in one direction and the other in the opposite direction. This makes sense, but air density remains a concern. The two rotors are shown operating in this film clip:

 

JPL continues:

NASA is sending a helicopter to Mars.

The Mars Helicopter, a small, autonomous rotorcraft, will travel with the agency's Mars 2020 rover mission, currently scheduled to launch in July 2020, to demonstrate the viability and potential of heavier-than-air vehicles on the Red Planet.

"NASA has a proud history of firsts," said NASA Administrator Jim Bridenstine. "The idea of a helicopter flying the skies of another planet is thrilling. The Mars Helicopter holds much promise for our future science, discovery, and exploration missions to Mars."

The Mars Helicopter is a technology demonstration that will travel to the Red Planet with the Mars 2020 rover. It will attempt controlled flight in Mars' thin atmosphere, which may enable more ambitious missions in the future.

U.S. Rep. John Culberson of Texas echoed Bridenstine's appreciation of the impact of American firsts on the future of exploration and discovery.

"It's fitting that the United States of America is the first nation in history to fly the first heavier-than-air craft on another world," Culberson said. "This exciting and visionary achievement will inspire young people all over the United States to become scientists and engineers, paving the way for even greater discoveries in the future."

Started in August 2013 as a technology development project at NASA's Jet Propulsion Laboratory, the Mars Helicopter had to prove that big things could come in small packages. The result of the team's four years of design, testing and redesign weighs in at little under four pounds (1.8 kilograms). Its fuselage is about the size of a softball, and its twin, counter-rotating blades will bite into the thin Martian atmosphere at almost 3,000 rpm - (revolutions per minute) - about 10 times the rate of a helicopter on Earth.

Actually, we find the last statement to be misleading. While it is true that many helicopters on Earth operate at around 300 rpm, for small RC (radio controlled) helicopters, some in fact do operate at about 3,000 rpm. The actual anticipated rpm for the Mars helicopter is 2,800 rpm. In the helicopter lift formula (Lift = CL ½ρV2S) discussed later, V is the rpm. Since it's squared, it's not a good to overstate it by 200 rpm. Comparing  a drone on Mars with a large helicopter on Earth is like comparing oranges with watermelons. So let's pause here and look at the rpm figures for rotary aircraft on Earth.

Full size helicopters main rotor spin between 250 and 600 rpm. The larger the rotor the slower it turns. The tip speed of the blade is the limiting factor.

Model helicopters on Earth operate at up to 3,000 rpm.  Since the envisioned helicopter for Mars is about 1.8 kg (under 4 pounds on Earth - under 1.508 pounds on Mars) the model figure pertains to it on Earth, and on Mars.  The rotor diameter for the Mars Helicopter is 1.21 m (that is, its tip radius is 0.605 m). Here are some rpms and blade lengths (radii) of RC devises and for helicopters that can carry people:

450 RC: 110 m/s (3000 rpm, 0.35 m tip radius)
500 RC: 126 m/s (2500 rpm, 0.48 m)
600 RC: 133 m/s (1900 rpm, 0.67 m)
700 RC: 155 m/s (1900 rpm, 0.78 m)
Hughes MD530F: 213 m/s (490 rpm, 4.15 m)
Bell 206: 210 m/s (394 rpm, 5.08 m)
Sikorsky UH-60L: 221 m/s (258 rpm, 8.18 m)

 JPL continues:

"Exploring the Red Planet with NASA's Mars Helicopter exemplifies a successful marriage of science and technology innovation and is a unique opportunity to advance Mars exploration for the future," said Thomas Zurbuchen, Associate Administrator for NASA's Science Mission Directorate at the agency headquarters in Washington. "After the Wright Brothers proved 117 years ago that powered, sustained, and controlled flight was possible here on Earth, another group of American pioneers may prove the same can be done on another world."

The helicopter also contains built-in capabilities needed for operation at Mars, including solar cells to charge its lithium-ion batteries, and a heating mechanism to keep it warm through the cold Martian nights. But before the helicopter can fly at Mars it has to get there. It will do so attached to the belly pan of the Mars 2020 rover.

"The altitude record for a helicopter flying here on Earth is about 40,000 feet. The atmosphere of Mars is only one percent that of Earth, so when our helicopter is on the Martian surface, it's already at the Earth equivalent of 100,000 feet up," said Mimi Aung, Mars Helicopter project manager at JPL. "To make it fly at that low atmospheric density, we had to scrutinize everything, make it as light as possible while being as strong and as powerful as it can possibly be."

OUR COMMENT: Again, we find the information provided to be less than straightforward. The record altitude for a full sized heliicopter on Earth was set at 40,820 feet on June 21, 1972.  Jean Boulet of France flew a single-turboshaft Aerospatiale SA 315B Lama, which had been stripped of all unnecessary equipment to reduce weight. He could have possibly gone higher, but the Lama's engine flamed out, which necessitated an autorotation to the ground and an unintentional additional record: the longest successful autorotation. However we have not seen small, RC helicopters get to anywhere near that alttitude.

In 2012 a record altitude was achieved for an RC plane at 4,930 meters/16,177 feet - nowhere near the 100,000 feet NASA is talking about. See 4931m 16177ft RC plane altitude record at https://www.youtube.com/watch?v=AKZj-7fCoMk. However, that's for a fixed wing aircraft. An initial search online for a record altitude for an RC helicopter did not come up with anything concrete.  A concern was seen with worries about losing sight of the helo, and having it fall on people or property below (not problems for the envisioned Mars test flight). The starting altitude was often mentioned, but it did not appear to be a major problem (at least up to altitudes of about 11,000 feet).

 JPL continues:

Once the rover is on the planet's surface, a suitable location will be found to deploy the helicopter down from the vehicle and place it onto the ground. The rover then will be driven away from the helicopter to a safe distance from which it will relay commands. After its batteries are charged and a myriad of tests are performed, controllers on Earth will command the Mars Helicopter to take its first autonomous flight into history.

"We don't have a pilot and Earth will be several light minutes away, so there is no way to joystick this mission in real time," said Aung. "Instead, we have an autonomous capability that will be able to receive and interpret commands from the ground, and then fly the mission on its own."

The full 30-day flight test campaign will include up to five flights of incrementally farther flight distances, up to a few hundred meters, and longer durations as long as 90 seconds, over a period. On its first flight, the helicopter will make a short vertical climb to 10 feet (3 meters), where it will hover for about 30 seconds.

OUR COMMENT: There are three altitudes of interest in earth. The first is hover ceiling out of ground effect (OGE). This is the point at which power available equals power required to hover at a given gross weight. Second is the hover ceiling in ground effect (IGE). Because ground effect reduces the induced power required, the IGE is much higher than the OGE ceiling. It sounds like NASA is counting on IGE to help them achieve flight above Mars. The third ceiling of interest is the maximum ceiling. This is the altitude in forward flight at the speed of minimum power. 

As a technology demonstration, the Mars Helicopter is considered a high-risk, high-reward project. If it does not work, the Mars 2020 mission will not be impacted. If it does work, helicopters may have a real future as low-flying scouts and aerial vehicles to access locations not reachable by ground travel.

"The ability to see clearly what lies beyond the next hill is crucial for future explorers," said Zurbuchen. "We already have great views of Mars from the surface as well as from orbit. With the added dimension of a bird's-eye view from a 'marscopter,' we can only imagine what future missions will achieve."

Mars 2020 will launch on a United Launch Alliance (ULA) Atlas V rocket from Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida, and is expected to reach Mars in February 2021.

The rover will conduct geological assessments of its landing site on Mars, determine the habitability of the environment, search for signs of ancient Martian life, and assess natural resources and hazards for future human explorers. Scientists will use the instruments aboard the rover to identify and collect samples of rock and soil, encase them in sealed tubes, and leave them on the planet's surface for potential return to Earth on a future Mars mission.

The Mars 2020 Project at JPL in Pasadena, California, manages rover development for the Science Mission Directorate at NASA Headquarters in Washington. NASA's Launch Services Program, based at the agency's Kennedy Space Center in Florida, is responsible for launch management.

For more information about NASA's Mars missions, go to:

https://www.nasa.gov/mars

DC Agle
Jet Propulsion Laboratory, Pasadena, Calif.
818-393-9011
agle@jpl.nasa.gov

Dwayne Brown / JoAnna Wendel
NASA Headquarters, Washington
202-358-1726 / 202-358-1003
dwayne.c.brown@nasa.gov / joanna.r.wendel@nasa.gov

2018-096  

OUR GENERAL COMMENTS. The information provided above is largely for public relations purposes. It is our experience that Public Relations (PR) at JPL and NASA often quote facts that are very wrong or incomplete. As we note in Section 1 of our report, Mars Correct: Critique of All NASA Mars Weather Data, for Mars Science Laboratory (MSL) PR folks published totally wrong, never changing for wind direction and speed for 9 months, and likewise never changing sunrise and sunset time for a similar period of time until we contacted Guy Webster at JPL and convinced him to alter the wind data to N/A and to alter sunrise sunset times to within one minute of our calculations. We would like to see the reports for projects like the helo attempt written by technicians who both understand their projects completely and who can write the overview given to the public. These overviews should not be dumbed down to the level of an 8th grader. Fortunately, we found much of what we needed at https://rotorcraft.arc.nasa.gov/Publications/files/Balaram_AIAA2018_0023.pdf with the article entitled Mars Helicopter Technology Demonstrator by J. (Bob) Balaram et. al (2018).

GRAVITY. In trying to understand how the weak gravity on Mars (3:71 m/s2 vs. 9.81 m/s2 on Earth) might help get the marscopter off the ground, we searched in vain for an answer in the JPL announcement but found it in the Balaram article. They note:

The mass of this first prototype was approximately 0.75 kg allowing free-flight under Earth gravity conditions. For the Mars Technology demonstrator EDM at approximately 1.7 kg, free-flight is not possible without the lower gravity of Mars partially compensating for its thinner atmosphere by requiring less lift to fly a vehicle than would be required on Earth. To test fly a vehicle on Earth that was designed for Mars, a gravity offload system must be used to effectively reduce the weight lifted by the rotors. The offload system consists of a constant force motor (implemented by closed-loop sensing of line tension) and a reel fitted with Dyneema filament.

        What is Dyneema filament? Dyneema and Spectra are lightweight high-strength oriented-strand gel spun through a spinneret. They have yield strengths as high as 240 kg/mm2 or 350,000 psi and density as low as 0.97 g/cm3 (for Dyneema SK75). High-strength steels have comparable yield strengths, and low-carbon steels have yield strengths much lower (around 0.5 GPa). Since steel has a specific gravity of roughly 7.8, these materials have a strength-to-weight ratios eight times that of high-strength steels. Dyneema was invented by Albert Pennings in 1963 but made commercially available by DSM in 1990.

THE MARSCOPTER TEST FLIGHT vs. THE AMES TEST FACILITY TESTING FOR DUST DEVIL SIMULATION. The JPL article didn't really tell us anything about the Mars Helicopter test flight, but the article by Balaram et. al (2018) was more convincing. The device was flown in a JPL 25-foot Space Simulator Chamber shown in JPL Figure 2A. The primary reason that we have to doubt JPL is what happened when NASA Ames tried to replicate dust devils on Mars with a fan in a space simulator at Ames in Mountain View, California. Ames failed. But we need more information about the fan blades and lifting dust is not the same as lifting a small toy-like helicopter in a low gravity environment. Frankly, if we are right about Martian air pressure being so much higher than NASA asserts (511 mbar at areoid vs. 6.1 mbar at areoid) , we might be able to get a helicopter to fly there that could carry people.

JPL Figure 2A - The 25-ft space simulator with Mars helicopter test equipment shown inside.

NASA Ames Test of Martian Pressures and Dust Devils 

An effort was made at the Ames facility to simulate Martian dust devils at a pressure of 10 mbar.  NASA (2005 article)1states that, “The high-pressure air draws thin air through the tunnel like a vacuum cleaner sucks air. Scientists also compare this process to a person sucking water through a straw. The resulting simulated Mars wind moves at about 230 feet per second (70 m/s).”  Actual recorded dust devil wind speeds seen on Mars by Pathfinder and Phoenix were about 6 m/s.24 Seventy m/s is 252 kilometers per hour, nearly the strength of a category 5 hurricane.  NASA Ames was unable to replicate a dust devil with a fan spinning at the 10 mbar pressure level. They state that “the simulated (10 mbar) Martian atmosphere in the wind tunnel is so tenuous that a fan would have to spin at too high a speed to blow thin wind through the test section.” As such, it becomes harder to accept that dust devils can occur in such low pressures. The problem becomes more severe when we see Martian dust devils operating at even lower speeds, or on Arsia Mons where pressure is supposed to be ~1 mbar.

Figure 3 - NASA Ames was unable to form a dust devil by using a fan.

Is it fair to compare fan blades that could not lift dust at Ames with blades on a helicopter that must lift a helicopter at similar low pressures? First let's look at the issue of particle size with respect to dust devils on Mars. The following is taken from Section 1.7 of our Report, Mars Correct: Critique of All NASA Mars Weather.

1.1.7 Dust Particle Size – The Problem of Martian Dust <2 Microns and Wind Speeds

Balme and Greeley3 also state, “The Martian atmosphere is thinner than Earth’s… so much higher wind speeds are required to pick up sand or dust on Mars.  Wind tunnel studies have shown that, like Earth, particles with diameter 80-100 μm (fine sand) are the easiest to move, having the lowest static threshold friction velocity, and that larger and smaller particles require stronger winds to entrain them into the flow.  However, much of Mars’ atmospheric dust load is very small, and the boundary layer wind speeds required to entrain such fine material are in excess of those measured at the surface (Magalhaes et al., 1999).4 Nevertheless, fine dust is somehow being injected into the atmosphere to support… haze and … local… and global… dust storms.”

The problem of dust particle size is more serious than indicated above.  Optimum particle size for direct lifting by the wind (with the lowest threshold velocity) is around 90 μm. This requires a wind at 5 meters altitude to be around 30-40 m/s. For smaller particles like the 1 μm size dust typically suspended in the air over Mars, the threshold velocity is extremely high, requiring enormous wind speeds (>500 m/s) at 5 m altitude which would never occur.  It is thus argued that saltation must be crucial to the lifting of very small particles into the air (Read and Lewis, 2004, 190).5

Saltation occurs when large particles are briefly lifted into air by surface winds, and then soon fall out by sedimentation.21 On impact with the surface, they may dislodge smaller particles and lift them into the air.  Read and Lewis indicate that the velocity that fine sand (~ 100 μm) would have on impact is only about 50 to 80 cm per second (1.8 to 2.88 kph).5

       Everywhere we look the weather plainly seen on Mars does not match what would be expected with an average pressure of 6.1 mbar/hPa at areoid (the Martian equivalent of sea level). No wonder Ames could not replicate dust devils if they used the correct particle size, expected pressure, and typical or even the most extreme winds seen on Mars.

       Dust particles are held together by static attractions. When the particles are as small as those on Mars, they may be hard to pull apart, especially if we accept the standard air pressure published by NASA (which we do not). There is no need to overcome this force to fly a small helicopter.

THE MARS HELICOPTER AND FLIGHT IN SUCH THIN AIR. When we first heard about this project we were tempted to dismiss it as likely impossible in the air density that NASA claims is true. We actually think that air density and pressure are about two orders of magnitude than what they tell us. It's not just because Ames couldn't replicate dust devils at 10 mbar, but because rapidly filled MER Spirit tracks required wind speeds of 80 mph at the assumed low pressures. These winds were never recorded on Mars. Nor could NASA explain drifting Barchan sand dunes. There are dust devils on Arsia Mons to altitudes of 17 km above areoid, spiral storms with 10 km eye-walls above Arsia Mons and similar storms above Olympus Mons (over 21 km high). Other reasons include extreme dust storm opacity, snow at Phoenix and elsewhere that descends 1 to 2 km in only 5 or 10 minutes, excessive aero braking, liquid water running on the surface in numerous locations at Recurring Slope Lineae (RSL) and stratus clouds 13 km above areoid.  For these reasons we argue for an average pressure at areoid of ~511 mbar rather than the accepted 6.1 mbar.  But, for the moment, let's suppose that we're wrong. Returning to the Balaram article. They wrote:

The mass of this first prototype was approximately 0.75 kg allowing free-flight under Earth gravity conditions. For the Mars Technology demonstrator EDM at approximately 1.7 kg, free-flight is not possible without the lower gravity of Mars partially compensating for its thinner atmosphere by requiring less lift to fly a vehicle than would be required on Earth.

       What the above statement tells us is that the truth about the ability to fly in low pressures here is not a matter of intuition. It's a matter of math, but unless the Mars Helicopter fails to lift off due to pressure even lower than NASA advertises, it's irrelevant.  The helicopter can certainly fly at the pressures we envision.

       One matter that is disturbing centers around the three potential landing sites for the 2020 mission.  We have already been to Columbia Hills (Gusev Crater) which is home to the Spirit Rover. While the Mars Helicopter is not considered to be mission critical, we would rather see a landing spot in a much lower area, one associated with running water (at the recurring slope lineae - RSL) and one where there is clearly enough air density to allow for flight of the helicopter even if NASA is right about air pressure - someplace like the Hellas Crater or in the Valles Marinaris.

These three places on Mars are potential landing sites under consideration as the destination for the Mars 2020 rover mission.
i
 

Final Three Landing Sites

GAMES NASA PLAYS WITH PRESSURES RECORDED AND PRESSURE SENSOR RANGE. Here we will start by asserting would should be ludicrous, but what we can prove to be true. Not all Martian air pressures published by NASA come from Mars, or are the product of NASA efforts. Many of them come from Roffman webs sites. We do not hack into NASA, we just challenge what their REMS (Rover Environmental Monitoring Station) Team in Spain publishes about the weather. We put up a print screen of their claims, and then sit back to watch them react to it and alter it as we predicted they would. Then we publish the print screen (often with accompanying humor/sarcasm) showing what they did. We also track their changes and update our Report, Mars Correct: Critique of All NASA Mars Weather Data to continuously show all such pressure changes. Table 1 below has a record of all such pressure changes made by NASA after their paid us a visit. This Table does not imply that we agree with the final pressures they give. We think they are all pure nonsense. What the Table really documents is that the Roffman Team is able to predict political changes based not on science, but on the need to deceive the public in a consistent manner.

TABLE 1 – Pressures revised by JPL/REMS after we highlighted them or published them in earlier versions of our Report

Date

MSL Sol

Ls

Initial Pressure Reported

Pressure for the previous sol

Final Pressure Reported after JPL Revisions

Aug 25, 2012

19

160.4

785 Pa

 

719 Pa– then changed to N/A

Aug 27, 2012

21

161.4

790 Pa

N/A

741 Pa

Sept 1 to Sept

5, 2012

26

164

 742 to 747 hPa

74200 to 74700 (Pa)

743 Pa

745, 743, 745, 747 and 747 Pa

Sep 12, 2012 (This date later changed to 9/11/2012)

36

169.5

799 Pa

749 Pa

750 Pa

Sep 16, 2012

(date later altered)

39

172.3

804 Pa

750 Pa

753 Pa - then changed to 751 Pa 

 

Oct 3, 2012

Series alteration starts here and goes to 10/12/2012

57

181

779 Pa

770 Pa

769 – Pa. Note the steady progression without reversals that were seen between 10/3/2012 and 10/12/2012 in initial results. This series looks very fudged.

Oct 4, 2012

58

182

779 Pa

 

769 Pa

Oct 5, 2012

59

183

781 Pa

 

771 Pa

Oct 6, 2012

60

183

785 Pa

 

772 Pa

Oct 7, 2012

61

184

779 Pa

 

772 Pa

Oct 8, 2012

62

184

782 Pa

 

774 Pa

Oct 9, 2012

63

185

786 Pa

 

775 Pa

Oct 10, 2012

64

186

785 Pa

 

776 Pa

Oct 11, 2012

65

186

785 Pa

 

777 Pa

Oct 12, 2012

66

187

781 Pa

 

778 Pa

Nov 11, 2012

95

204

815.53 Pa

822.43 Pa

822 Pa

Dec 8, 2012

121

221

865.4 Pa

867.5 Pa

869

Feb 19, 2013

192

267

940 Pa – a high until now. Pressures had been declining since a high of 925 Pa in late January 2013.

921

N/A

Feb 22, 2013

195

269

886 Pa – quite a large drop

Last 2 reports were 940 Pa on Feb 19 and 921

Pa on Feb 18, 2012

N/A

Feb 27, 2013

200

272

937 Pa

917 Pa

N/A

May 2, 2013

262

311

900 Pa

868.05 Pa

N/A

Aug 21, 2013

370

9

1,149 Pa

865 Pa

865 Pa

Aug 27, 2014

731

185

754 Pa

771 Pa

771 Pa

Oct 11, 2014

775

211

823 Pa

838 Pa

838 Pa

April 16, 2015

957

326

823 Pa

N/A  - next sol 848 Pa

N/A

Nov 10, 2015

1160

66

1177 Pa

898 Pa

899 Pa

Nov 12, 2015

1161

66

1200 Pa

899 Pa (revised)

898 Pa

April 2, 2016

1300

131

945 Pa

753 Pa

752 Pa

April 3, 2016

1301

131

1154 Pa

753 Pa (2 sols earlier, 751 Pa on Sol 1302

752 Pa

Oct 17, 2016

1492

242

921 Pa

906 Pa

910 Pa

Oct 23, 2016

1498

242

897 Pa

909 Pa

907 Pa

Oct 27, 2016

1502

249

928 Pa

903 Pa

907 Pa

Jan 10, 2017

1575

296

860 Pa

868  Pa

871 Pa

Feb 10, 2017

1605

314

815 Pa

850 Pa

846 Pa

Aug 13, 2017

1784

46

1294 Pa

879 Pa

883 Pa

Mar 24, 2018

2001

147

913

717

716

Mar 25, 2018

2002

148

1167

913 revised to 716 715

Table 1 shows some (not all) of how JPL/REMS altered off the curve data for August and September 2012 and August 2013 and on through at least May 31, 2018, after we either brought the deviations up to JPL Public Relations Director Guy Webster, or published them on our davidaroffman.com and marscorrect.com websites. Figure 4 below illustrates how the March 25, 2018 pressure shown on Table 1 was handled with print screens and humor on Roffman websites.

        How serious does NASA take Roffman efforts? NASA Ames visited our sites about 2,000 times in the last three years. I maintain records of almost all their visits, though I generally don't show the last two or three digits of the IP addresses they use only because I don't want to get the likely mid-level fans we have there get fired. It's rather like how I feel about the FBI. Most FBI agents are heroes, but as President Trump constantly reminds us, the people at the top of the FBI have, for several years now, been corrupt. Everything published by NASA about Martian pressure has long been corrupted.

       Evidently NASA knows something about the true history of Mars that they prefer to keep from the public.  They are trying to figure out how to handle the issue as is perhaps evident in Figure 5 recently published by JPL. It summarizes the upcoming NASA Mars Rover mission set to launch in 2020. Figure 5 advertises that the mission will look at wind speed and direction, temperature and humidity, and the amount and size of dust particles on Mars. Figure 5 makes no mention of pressure. Without pressure/air density, their wind speed and humidity data will likely be meaningless, again.

       The true air pressure on Mars, coupled with the motivation for hiding it, are likely among the greatest secrets held by our Government. However, I have evidence that there are other governments who know the true figure too. I believe there is an international Establishment with a vested interest in keeping the truth from the general public, but not necessarily from each other. For example, despite all the public posturing by the Democratic and Republican parties about who is tougher on Russia, the reality is that Americans, as of 2018, reach the International Space Station via Russian rockets launched from Kazakhstan. Further, American military satellites often launch from here in Cape Canaveral with the use of Russian RD-180 rocket engines.

Figure 4 Top half - Original REMS data for MSL Sols 1998 to 2002. Bottom half - NASA was forced to change their pressure data to move more in line with what we predicted that they would publish.

       

Figure 5 - What's missing on this JPL summary of weather measurements for NASA's 2020 Mars Rover? Pressure.

         As written above, Figure 5 makes no mention of pressure. Without pressure/air density, their wind speed and humidity data will likely be meaningless, again.  It is possible that JPL will see this article and follow their Standard Operating Procedure - revise the wording or delete it. Although the first page of this link, as of May 31, 2018, showed nothing about pressure, the ability to measure pressure up to 1,150 Pa (11.5 mbar) is mentioned later in the article where it states:

Located inside the rover body and connected to the external atmosphere via a tube, a pressure sensor (PS) collects pressure measurements. The tube exits the rover body through a small opening with protection against dust deposition. Its measurement range goes from 1 to 1150 Pa with an end-of-life accuracy of 20 Pa (calibration tests give values around 3 Pa) and a resolution of 0.5 Pa. As this component is in contact with the atmosphere, a HEPA filter is placed on the tube inlet to avoid contaminating the Martian environment.

       This figure is exactly the same as the original figure given out by the REMS Team for MSL. As Table 1 shows above, the 1,150 Pa pressure was exceeded several times on REMS reports, but every single time they exceeded it, and we pointed it, they revised it down. NASA did more than revise the pressures down. It also revised the highest pressure that could be measured by the Vaisala pressure transducer. We document this fully (with print screens) in Section 14.6.3 (Mixed messages about the range and sensitivity of pressure sensors sent to Mars) of our Mars Correct report.

       Nathan Mariels first brought the following contradiction to our attention: First let's look at a statement that backs the 1150 Pa figure: In Section 11 of the REMS Calibration Plan (Document No, CAB-REMS-PLN-002, Issue 002, it states: 

REMS shall measure the Ambient Pressure in the range of 1 to 1150 Pa with a resolution of 0.5 Pa and accuracy of 10 Pa BOL and 20 Pa EOL. Requirement 012 (PLD-20), REMS shall measure the Ambient Pressure at a minimum sampling rate of 1 Hz for at least 5 minutes each hour continuously over the mission.

       But, in their Abstract to the American Geophysical Union for the Fall 2012 meeting the FMI states:

The pressure device measurement range is 0 - 1025 hPa in temperature range of -45°C - 55°C, but its calibration is optimized for the Martian pressure range of 4 - 12 hPa.

       Note: 1025 hPa = 1,025 mbar. So, while it was supposedly optimized for 4 to 12 (not 11.5 mbar – meaning that the problem is not one of a sliding decimal place), it was still capable of measuring up to 1,025 mbar. Again, average pressure on Earth at sea level is 1,013.25 mbar. This is, to borrow a phrase from the Wizard of Oz, a horse of a different color.

       To handle pressures over 1,150 Pa, REMS also published a figure of 1,400 Pa. Specifically, in 2017 they wrote that:

"The pressure sensor measures atmospheric pressures in the range of 0 -1400 Pa with beginning of life accuracy circa 3 Pa. Its relative accuracy (repeatability in the time scale of hours) is less than 2 Pa and resolution max. 0.2 Pa."

       Mariels also pointed out a 2 order of magnitude pressure unit conversion error for Viking 1 and 2 pressures. The Global Electric Technology CEO wrote:

Pa is not equal to hPa. From Viking logs: "Pressure mb = millibars, 1 mb = 100 hPa, where hPa = hecta Pascals" This is incorrect.    1 mb = 1 hPa = 100 Pa. The above error was repeated on every data set for Viking 1 and 2.

SUMMARY

       My first hunch was to check the formula for helicopter lift. For the record it's Lift = CL ½ρV2S where CL is the lift coefficient which reaches its maximum value at the critical angle of attack (stall angle of attack), and the dynamic pressure is ½ρV2. The collective angle can range from -4.5 deg to 17.5 deg and the cyclic angle has a range of ±10 deg. Within the ½ρV2 term is ρ which is the air density. This particular figure is at the center of our 8+ year fight with NASA. The Balaram article offers an air density on Mars as 0.0175kg/m3, but does not include the exact landing altitude below aeroid for this figure, and there are as of June 1, 2018 still three possible landing sites.  Air density is required to calculate air pressure. V is the true air speed. In helicopter terms this is rotor rpm (2,800 revolutions per minute). Note that V is squared. S represents the surface area of the airfoil.

       I see that as I write this article on May 31, 2018 at 15:56 Pacific Time NASA Ames was reading the working draft. I would appreciate it if they would publish something with the exact, CL and surface area of the air foils, however, again, NASA-given pressures (and related air density) cannot be taken seriously when some of them are mere responses to critiques coming from my home. By the way, the IP addresses used by Ames (they always use the collocated Google at Mountain View, CA when accessing our articles) on May 31, 2018 at 15:56 Pacific Time start with the most common 66. number, but finish with .122 and .124. While NASA Ames IPs often reverse into DoD, these numbers reversed into Panjin, China and Rizhao, China. Early on June 1 there was a similar visit with a number ending in .120 that backed into Qinhuangdao, China. Ames, please check to make sure that you are not being hacked into.

       When it comes to Martian air pressure NASA errors are not the exception. They are the rule. As the European Space Agency had learned, if they follow NASA on this issue (as they did with the ExoMars 2016 Schiaparelli lander), it costs them a billion dollar lander. If they follow what we write, as they did when they raised the orbit of the ExoMars 2016 orbiter (citing "excessive Mars' atmospheric density"): they can save a mission. One final warning - the problematic Vaisala pressure sensor used on Mars Phoenix and MSL is apparently in line for further use on ESA's ExoMars 2020 and the NASA 2020 mission to Mars. This, we believe, will likely be a fatal mistake. We have reason to believe that the problems associated with the sensor may extend to some of the personnel associated with them. I have seen the U.S. House of Representatives (IP 137.18.102.5) visit our articles within the last week (5/30/2018). I strongly recommend that they thoroughly investigate all the data we have backing corrupted Mars weather data. The efforts made to keep the truth about Mars from being known is not, I believe, merely a Curiosity. Rather, the motivation behind these efforts is likely to expose everything that's wrong with the Deep State. As our President insists, it's time to drain the swamp.

 

REFERENCES

1Dunbar, Brian. "NASA Simulates Small Martian 'Dust Devils' and Wind in Vacuum Tower." NASA. NASA, 03 Mar. 2005. Web. 10 Feb. 2015. http://www.nasa.gov/centers/ames/research/exploringtheuniverse/vaccumchamber.html

2Ellehoj, M.D., Gunnlaugsson H.P., Taylor  P.A.,Gheynani, B.T ., Whiteway, J., Lemmon , M.T., Bean,  K.M., Tamppari, L.K., Drube1, L., Von Holstein-Rathlou, C., Madsen, M.B., Fisher ,D, & Smith, P. (2009). Dust Devils and Vortices at the Phoenix landing site on Mars.  40th Planetary and Lunar Conference. Retrieved from http://www.lpi.usra.edu/meetings/lpsc2009/pdf/1558.pdf

3 Balme, M., Greeley R. (2006), Dust devils on Earth and Mars, Review Geophysics., 44, RG3003,doi:10.1029/2005RG000188. 

4 Magalhaes, J.A., Schofield, J.T., & Seiff, A. (1999). 

         Results of the Mars Pathfinder atmospheric structure investigation, J. Physics. Res., 104, 8943-8955

http://gaspra.la.asu.edu/dustdevil/proceed/Balme_and_Greeley_DD_ms.pdf

5 Read, P. L., & Lewis, S. R. (2004). The Martian Climate Revisited, Atmosphere and Environment of a Desert Planet, Chichester, UK: Praxis.

6 Bagnold, R. A. (1954). The Physics of Blown Sand and Desert Dunes. London, Methuen.