Good afternoon everyone, I’m RJ Pfammatter from Taos New Mexico. I used to be an aerospace engineer, working on aircraft motors, jets for Pratt Whitney and other companies. And presently I am an Artist. My topic this afternoon is about Piloted Flights to Mars. First of all I would like to take a few moments to talk about the aircraft industry and how it relates to going to Mars. There is a scenario that is analogous to the progression we will make in our Mars vehicles whether we launch from the earth’s surface or from the International Space Station, the pilots tasks will be the same. When I was a kid, I flew to Europe in a four engine piston aircraft. It took 27 hours, and it was necessary to make two stops for fuel. The pilot was nice enough to invite me to the cockpit. I think I was sitting in the engineer’s seat. It was very interesting seeing the spectacular land fall, the ocean and finally Great Britain. Today we fly across the ocean non-stop with a 2 engine aircraft routinely in comfort and with quality hardware. We have safety and reliability and of course the engines are no longer piston driven but use gas turbines with over 52K thrust. The reliability is such that only 2 engines are required. In a similar manner, we will evolve more reliable ways to fly to Mars and like the aircraft industry, the journey will become more routine. Of course this is a very special year. It marks the 100th anniversary of powered flight at Kitty Hawk. And the planet Mars is very close to earth, closer than it has been for a very long time, only 34,600,000 miles. And so I decided that it was a special occasion and important to do a presentation on Mars and come to Eugene, Oregon. We have come a long way since Kitty Hawk. The Wright brothers, they were an unusual pair. I like to think that they had that little flying machine all figured out; they were thinking in a different way than anyone else that was trying to fly at that time. Since that time, the aircraft industry has evolved in great strides, including the Space Shuttle and entering space itself. During WWII fighter aircraft, engines and munitions came to be designed so that large loads could be flown long distances effectively. Our flight systems today are designed for reliability and safety and from Dr. Zubrin’s book we know that with today’s technology we can go to Mars. It would be nice if we could go there and not have to wait 100 years to do so. I always like to have the example of Richard Fehnman who was one of the great physics teachers. He also helped solve the riddle of the Challenger accident. If he was still alive today, he certainly would be enthusiastic for going to Mars. And the same for Carl Sagan. Both of these men were very good in their fields, had open minds and interested in the future and possible traveling to Mars.
Next thing I’d like to talk about is space itself. It is a very different place than the atmosphere of earth. Space offers a lot of advantages over flying around in the air, here on earth. There is no need for airfoils (wings) for example, nor control surfaces and engines don’t need to be shrouded with complicated nacelles (casings). Also there is no friction in space. So when we fly around in space the systems are actually simpler - not unlike flying around in a submersible in the ocean for example. So any thrust imparted by the engines is directly converted to higher velocities of the spaceship. The pilot will experience smaller forces for longer periods depending on the cruising speed to Mars. When we take off in an airplane, for example, our acceleration is high for a short period say less than 10 minutes. The engines put out a lot of thrust with consequent usage of a lot of fuel. In space on the other hand, the acceleration is much smaller and the engine’s need to be more efficient. High specific impulse ( a measure of efficiency) is a must so that fuel usage is kept at a minimum. As a consequence, the thrust is small and the pilot would take maybe 5 - 10 days to reach the cruising velocity on the order of 6 - 12 miles/second greater than the earth’s speed around the sun. It could be said that F=ma will get us on our way. This of course is the famous Newton equation which relates the mass of the body and its acceleration to the force or thrust in this case imparted by the spaceship engines. When we go to Mars it will be a beautiful experience, the stars, Moon, Earth and Mars receding or coming closer. In our spaceship large windows ( I see no reason for having tiny port holes) will make the journey spectacular. Unlike the International Space Station, endlessly circling the earth, a voyage to Mars will be like sailing to an unknown land with many interesting things happening along the way. Those on Earth will watch and hear with great fascination as the journey unfolds. Now lets imagine and step into that time when we go to Mars. The International Space Station in the future might be employed doing operations and other tasks besides scientific experiments. A space garage would be a nice addition to the space station. There we could check out our vehicle in a shirt sleeve environment without cumbersome spacesuits. The pilot could go around the vehicle checking things out in a similar fashion a jet pilot checks out his or her aircraft on the ground.
With the ship in LEO (Low Earth Orbit) and ready to go, there are many paths to Mars. Some of the details of which I would like to talk about next. The pilot as his earthly counterpart will rely on a planetary positioning system not unlike the Global Positioning System used today. If we consider Keplers equations of planetary position which describe the motion of bodies moving around the sun. And the fact that Mars has a greater elliptical orbit than our earth, the consequence of which causes Mars to be in a favorable position every 2 or 3 years. Because of this, a trip to Mars can be more efficiently traveled using less fuel than other times. At the same point in its relative orbit, the earth is going faster than Mars by 2 or 3 miles/sec. When flying between any two points on earth, the captain of an airplane frequently flies over the poles to save time and fuel. So in a similar fashion a ship going to Mars will factor in the mass, the stores used for propulsion, the final cruising speed, and direction taken after a sling shot around the moon and/or solving Kepler’s equation for the particular elliptical path used. The pilot would input these things into the computer and then file a flight plan. In this scenario, the vehicle I talk about is better described in the lecture titled Mars Fast Forward which was presented at the convention in Toronto in 2000. It has been published in book form as the proceedings that took place there. In that particular case there are 2 or 3 astronauts onboard, which is probably the least number required for a mission since each member would need to be in the pilots seat between 4 to 6 hours at a time. A robot would be employed probably as co-pilot at all times. The movie 2001 comes to mind and the importance of Hal the computer, who provided valuable assistance in the smooth operation of the ship. The engines would be variable thrust and gimbaled, and also probably be the type that are augmented depending on fuel available. The importance of robotics can not be underestimated and will greatly relieve the crew in its long journey.
The journey itself I want to describe next: The commander of the ship as well as the pilot in control at any one time would have the safety of the flight as his or her first priority. Although there is no weather as such in space, the solar flares produced by the sun are an ever present danger to both the crew and the sensitive electronics aboard the space craft. This activity needs to be monitored at all times. When they occur, the ship would need to be turned so that the reactor faces the sun. This of course is because of the shielding between the crew and the reactor module (which produces the electricity required for the mission) is a natural barrier against the radiation or flux produced during solar flare activity. In the case of this vehicle, this barrier is made of tanks of stored water. The other very important anomaly and danger is the probability of space debris crossing the path of the spaceship on its way to Mars. This hazard can be both optically detected or tracked by radar and monitored by the pilot and/or robot computer combination. In a ship traveling to Mars, I believe, it important, for that reason a number of independent hulls are required and utilized, not unlike the way a submarine is designed to be able to sustain damage and still operate under adverse conditions. When the pilot can not fly around the debris field and a pressure hull is compromised, the cockpit, as well as supporting computers and hardware needs to be moved to a separate compartment so that the mission can continue. Anyway, I further want to say that the crew also needs to be in good physical condition. The physical effects of the loss of gravity during space travel can affect bone and muscle loss. One way to counteract the loss of gravity is with a centrifuge. The space vehicle I envision has a centrifuge mounted underneath the space ship usable by crew members 3 or 4 hours every other day to maintain bone density as well as good health throughout the voyage. The commander in chief would be of course responsible for the medical condition of the crew. One of the crew would be a medical officer. Since this journey is probably longer than 2 months, its important that these functions be monitored in a useful manner. The engineering functions as well s the status of consumables would be largely automated and/or traced by means of the robot brought along.
I’d like to mention a little bit more about the path to Mars. If we could fly about a million miles per day, we could get there in probably less than 120 days. This is not unreasonable if our spaceship is light (low mass), cast off unwanted tanks and hardware as we bypass the moon and have efficient engines. These engines might be light weight ion type engines that are augmented with either methane or hydrogen. These fuels are generated on the way to Mars, minimizing storage and tank requirements. As mentioned before they would be very efficient and could be throttled up or down by the pilot. Approaching Mars the ship would turn around and slow down so as to be captured by Mars gravity.
It seems hard to believe that with the many adverse events, the eventuality of journeying to Mars will finally take place. With the Mars Society firmly in place and the addition of new members (true believers) in man’s greatest journey, joining our cause everyday, we will go to Mars. Not just with robots but with people from our planet earth.