Access to Space.

The following comprises the thoughts, views and considered opinions of AVG Aerospace Limited.

Access to space and the means of achieving this in an economical and commercially viable manner has occupied the attention of the world's aeronautical and space industry for decades but, not more so than now. At this time the race is on particularly in the United States to achieve Single Stage to Orbit flight in the form of a Reusable Launch Vehicle (RLV) with a payload, performance, economic and commercial capability that both addresses and satisfies the identified requirements of The Pentagon, NASA, USAF, Commercial and National Defense considerations.

Statement No.1: It is the considered opinion of AVG Aerospace that an economic and commercially viable SSTO/RLV Single Stage to Orbit Flight in the form of an economically viable Reusable Launch Vehicle is now possible using virtually, "of the shelf" aeronautical and aerospace technology.

Statement No.2: The lesson of the AVG is clear and is as applicable in this instance where the task is to achieve an SSTO/RLV with a payload and operational capability that can be achieved in a way that makes economic and commercial sense.

Statement No.3: The question might well be how? The lesson and the answer is, you must establish direct command control over the immediate air space completely surrounding the engine of the vehicle in the manner described in principle and as set out in, the "AVG CASE". This applies regardless of whether the Vehicle is propelled by a jet engine, ram jet or rocket. For the explanation as to why, see "The Problem" accessed from the Home Page of this site. Although, "The Problem" is identified as being that pertaining to Jet Powered Aircraft the same System's solution i.e., the AVG in principle also applies to SSTO, RLV's regardless of how they are propelled.

Statement No.4: To achieve anything approaching a solution of the SSTO/RLV challenge your system must recognize the critical need to establish direct connection between the end of the ACTION Half of the Vehicle's Motion System Cycle (the propelling nozzle jet engine or rocket in whatever form it may take) and, the Start of the REACTION half of the same Cycle i.e., as the Air mass either enters the Jet Engine or passes around the vehicle structure where the rocket is located. Rockets located wholly within the Vehicles structure will be unable to achieve the level Specific Thrust per unit of mass flow employed by its propulsion system that would be needed to off set the motion efficiency penalty the vehicle will suffer employing the use of rockets in this way. Hence, the limiting of its payload capability.

Statement No.5: Once a Motion Vehicle is required to operate within the earth's atmosphere at supersonic, hypersonic and escape velocity speeds its success in terms if its efficiency as a motion vehicle and its payload capability will both be determined and governed by how efficiently the utilization of the "Laws of Motion" are provisioned for in its design.

Statement No.6: The considered failings of the current attempts to achieve SSTO/RLV in AVG's judgement is caused by the failure to understand that in an extremely high performance Vehicle required to fly up throughout the earth's atmosphere from subsonic to escape velocity, that the dominant factor governing its economic viability will not be the physical efficiency of its means of propulsion or the aerodynamics of its structure but, the actual manner in which the rate of thrust is both delivered to and utilized by the Vehicle.

Statement No.7: Required to operate at these velocities within the earth's atmosphere means that the predominant component in the thrust equation: thrust = mass X velocity becomes its velocity component, consequently, the establishment of an integrated control system over the mass motion velocities of the ACTION and REACTION halves of the Vehicle's, Mass Motion System Cycle is critical to the establishment of an economically viable SSTO/RLV.

Statement No.8: The employment and use of any form of rocket propulsion as the primary source of thrust power in such a Vehicle renders establishment of the required motion/velocity integration between the ACTION of the rate of thrust power delivered and the RESULTANT Velocity of the surrounding Air Mass relative to that of the Vehicle itself making it impossible to achieve an economically viable SSTO/RLV in this way. This is particularly true if this form of propulsion is employed below 100,000 feet. Consequently, any purely rocket form of engine employed anywhere throughout the Vehicle's flight except beyond the fringe of space itself will not be able to economically achieve SSTO flight in the form of an economically viable RLV. In the opinion of AVG to attempt to do so in this way will inevitably prove to be far most costly than the proper utilization of existing conventional high performance pure jet engines in combination with a ram jet and AVG in combination makes possible.

Statement No.9: A rocket in terms of fundamental motion physics is no longer a rocket when employed as the means of propelling a vehicle but, is a Motion Vehicle in its own right. Bolt any form of rocket you choose to any form of Vehicle structure such as is being done now then, you are in affect, bolting together two entirely different forms of Motion Vehicle that are then forced to physically act as if they one and the same. They are not. As a direct consequence of this action the motion thrust losses incurred resulting from the total failure to achieve a direct control over the motion interaction between the rate of thrust delivered by the rocket forming the ACTION half of the Vehicle's, Motion System Cycle and, its RESULTING Velocity throughout the atmosphere will dramatically reduce the Specific Thrust force at the disposal of the Vehicle hence, its payload capability. (Reference: "The AVG Case").

Statement No.10: A Rocket has no place in such a vehicle that is required to achieve an economically viable payload capability necessitating a very high level of Specific Thrust that will be impossible to achieve operating when operating a Vehicle of this kind anywhere below 100,000 feet.

Statement No.11: Surely, something of this was learned from the lessons from the commercial failure the technically brilliant shuttle and, in its own way, the equally brilliant, Anglo- French Concorde!

Statement No.12: The United States Shuttle was the first quite admirable technological attempt at creating a commercially viable Space Vehicle. And, although technologically quite brilliant was nonetheless bound to be a commercial failure, hindsight, not at all. Consider, it required massive vastly expensive rocket assisted take-off also tremendous infrastructure and by the very nature of its mission required rocket engines to deliver its remaining very limited payload and then power its return back to earth in an almost, barely controllable, free fall state. The stark reality was and is that considering the way the state of the art technology was employed, in this instance, there was never any real possibility of it ever being able to achieve a payload capability that could conceivably make commercial sense. Nonetheless, it was and still is, a tremendous technologically brilliant achievement. And, herein lies a great technological paradox of our time if it is so technologically brilliant as acknowledged here why could the aerospace industry not have done a better job? The answer in part lies in the attitude, particularly in realms aeronautics, aerospace industry and NASA, that if they throw enough technologically motivated brains at a problem that the shear mental power directed at it will solve whatever the problem is conceived as being. The evidence of history shows this is not the case, consider:

• 1. Concorde, a technically brilliant commercial failure.
• 2. NASP, The United States, National Aerospace Plane, here again technically brilliant in conception but, economically impractical.
• 3. The following are a few of the concepts created in an endeavor to meet the specification for a commercially viable Single Stage to Orbit Reusable Launch Vehicle:
  
  
  
   
• A: Kistler, K-1 2- Stage Vertical Take Off, Parachute return Vehicle.
• B: Rotary, Rotan 1-Stage Vertical Take Off and Landing Vehicle.
• C: Kelly, Astroliner 2 Stage (Stage 2 non reusable) Horizontal Take Off with tow assistance & Landing.
• D: Pioneer, Rocket Plane, 2-Stage (Stage2 non reusable) horizontal Take Off (In flight refueling & Landing).
• E. Space Access, SA-1 2-Stage, 1st Ram Jet, Horizontal Takeoff & landing, 2-stage Reusable rocket.

This information was downloaded from: http://www.particle.kth.se/~lindsey/RLVCCountdown.html and are but a few of the concepts referred to in this document from the "particle.kth site. Each of the concepts mentioned here and the others that exist are all intended in their respective designs to meet the need for an economical SSTO/RLV, (Single Stage to Orbit/Reusable Launch Vehicle). Of those mentioned above and the others that exist, it would seem according to some other views that only the Space Access SA-1 comes anywhere close to meeting the desired criteria.

What is the lesson of the foregoing? The answer is not hard to find. Consider, each and every one of these concepts involved the engagement of quite tremendous technological skill and yet and are continuing to struggle, Why? If these enterprises are as technologically clever as they undoubtedly are, but as yet failing to solve the problem set, there can only be one answer. They do not understand the true nature of the problem to be solved. And yet, this hardly seems probable considering the totally different yet very considerable knowledge, experience and technical skills each of the companies involved bring to the task. If this is not the answer, what is? The clue to answer lies in the fact that these are tremendously talented companies involved here, not to mention, The Pentagon, NASA, USAF and the entire United States Aerospace Industry. The tremendous talents of the United States, as a Nation, enabled astronauts to travel to the moon and back and yet, is failing here, again why? The answer as to what the truth is lies in recognizing that you are failing in spite of your tremendous talent, and technical know how as, a Nation. Now, there can only be one possible reason for such uniformly poor results quite regardless of your undoubted abilities.

The sixty four billion $ dollar question is, what is it?

The answer is, something which has been accepted as an absolute truth underpinning the understanding of how the ultimate economic efficiency of both the physical and motion systems comprising a Vehicle particularly when required to act in combination in the forming of Motion Vehicle's, Motion System Cycle that is caused to fly, is in fact, incorrect. As a direct and inevitable consequence of such a fault, all of the technological effort invested in such Motion Vehicle projects will invariably incur costs out of all proportion to any gain achieved, resulting in a directly proportional reduction in the rate of return on the investment capital employed.

This we here at AVG submit is exactly where both the Jet Powered Aircraft and Aerospace Industries of the world are today.

Consider for a moment, the conventionally held definition and understanding of what a rocket is; excerpt taken from the Chambers Science and Technology Dictionary", (Aero-Space definition) reads as follows, 1. "A missile projected by a rocket system", 2. "A system, or a Vehicle, powered by reaction or rocket propulsion".

Consider, definition of rocket propulsion (Aero.) definition, "Reaction Propulsion using internally stored , instead of atmospheric oxygen for combustion.

Note: The foregoing is the physics description of a rocket, however, in terms of the Laws of Motion the rocket it is in fact a Motion System in its own right wherein its internal fuel mass is caused to leave the rocket engine in a highly accelerated, very high velocity heated gas state. The fact that the reactionary thrust force so produced is transmitted directly via a bolted means to some form of Motion Vehicle's physical structure thereby transferring and making its own Motion Thrust Force that of the Vehicle it is in fact powering in effect transforms the rocket into a Motion Vehicle in its own right. Consequently, you have in effect have bolted together two entirely differently acting, different functioning Motion Vehicles and, in so, doing force them to act as if they are one Motion Vehicle, which is not correct. For an explanation of this statement see "The Problem", accessed from this site's Home Page.

Exactly the same mistake is being made here as in the failure identified in the AVG Case, you are bolting together at least two entirely different MassMotion Vehicle systems each of which are entirely different in their operation and function and treating them in your designs as if they are in fact one. And, you are wondering why you are failing, or, you should be!

In terms of fundamental physics the air-breathing rocket concept is powered by a rocket in the conventionally held sense. The fact that this rocket discharges into a surrounding tube into which is entrained a mass of air from the surrounding atmosphere does not alter this truth. The fact that the entrained air mass in this way appreciably enhances the effectiveness of the thrust force delivered to the Vehicle by its rocketstill does not make this an air breathing rocket. And, herein lies the clue to the cause of the failure of this vast Aerospace Industry to establish a better command control over the economics of its entire endeavor more in keeping with its otherwise technical brilliance. It is its failure to understand and appreciate the actual problem that requires to be addressed before access to space can ever be economically achieved.

Technology is not the limiting factor in the challenge that is the SSTO/RLV but, how best to utilize this brilliance.

Consider, you are technologically brilliant, this you have demonstrated time and time again, however, when you move into the realm of supersonic, hypersonic and escape velocity speeds employing, vehicles required to operate in two entirely different environments then, the manner you elect to utilize the brilliance that has so far served you so well, requires to be completely rethought. It has not happened.

Consider: Of all of the concepts currently under development or consideration not one with the exception of the so called, air-breathing rocket complies with any of the criteria identified in statements No's, 3, 4, 5, 6 and 7. And, even in this instance the answer is only half-right then proceeds to throw the advantage away, revealing that the problems to be addressed and overcome are not properly understood.

It is of course perfectly true that these are just the opinions of AVG Aerospace.

Consider, the rocket provides the physical thrust force that creates the forward motion of the Vehicle and in so doing forms the ACTION half of its Motion System Cycle. The resulting forward motion of the Vehicle RESULTS in this instance creation of a rearward flowing Air Mass that in interaction with the physical structure of the Motion Vehicle forms the REACTION half of its Motion Cycle.

Consider, when the rates of motion action between the ACTION and REACTION halves of its Motion Cycle are the same then its efficiency as a Motion Vehicle is 100%.

Consider, the physical efficiency of any Motion Vehicle is determined by how efficiently the thrust power delivered to the thrust bolts of the Vehicle in terms of the Vehicle's fuel consumption, is used. This is normally expressed in terms of the weight of fuel consumed, per unit of thrust, per unit of time. However, this is a Motion Vehicle not a power station and once the thrust is delivered to the Vehicle it is how efficiently the system means is, by which this thrust force is translated into motion that determines the Vehicle's actual Motion Efficiency and payload capability. Consider: The specific manner we elect to both treat and utilize the very unique relationship in the Creation between Mass and Velocity as in the thrust equation i.e., thrust = mass X velocity is critical. In this specific instance, the velocity component of the equation i.e., the velocity component becomes the dominant factor in the thrust equation particularly as in this case where the vehicle so propelled is required to operate at speeds above Mach .87. Failure to get this balance between the interacting velocities of the ACTION and REACTION halves of the Vehicles Motion System Cycle will result in a rate of Specific Thrust loss that can go up quite dramatically once above supersonic speed and, almost exponentially above hypersonic speeds.

Consider, once the thrust power is delivered to the structure of the Vehicle however its is delivered, the physical contribution to the performance of the Vehicle is in a sense ended; it is true of course, that the physical efficiency of its delivery determines the power at the disposal of the Vehicle and potentially what can be achieved in terms of its speed, and payload capability. And, the rate of fuel consumption determines how long the physical performance can potentially be maintained. However, as Motion Vehicle its Motion efficiency i.e., how fast it can fly and how far in response to the rate of thrust force delivered to it, is FINALLY determined by how efficiently the Laws of Motion are utilized. And, this final determination of the Vehicle's Resultant Motion is far more critical than any mass or weight saving could possibly have upon either the speed or payload capability of the vehicle.

Statement The entrainment of an air mass in support of the rocket in the manner described does not add one single unit of thrust to the thrust power actually delivered by the rocket to the Vehicle but, does dramatically improve the utilization of the thrust so delivered.

Consider: If the understanding offered here is correct then the evidence of this as in the "Case" made against the World Jet Powered Aircraft Industry elsewhere in this site must be there for all to see if, we could but conceive it. The question is "where can we expect to find the evidence as to the truth of this statement"? The answer off course is, at the frontier of the understanding invested in the considered best technical solution currently on offer in response to the challenge posed by The Pentagon, NASA, USAF, Department of Defense and Commerce. In this instance, this is regarded by those who are supposed to know about such matters as, the concept utilizing the so-called, air breathing rocket system.

The NASA description and case for the "Air Breathing Rocket Propulsion System concept is as described in the following Space Transportation article (http://std.msfc.nasa.gov/newsarchive/airroaket.html) which reads;

"Taking another step forward making future space transportation more like today's air travel, NASA's Marshall Space Flight Center in Huntsville, Ala., and its industry partners have completed a series of successful tests on air-breathing rocket engines. The latest ground testing focused on engine performance during low speed portions of the flight, when high thrust levels are needed to push the air breathing rocket through the earth's atmosphere. An air-breathing – or rocket based, combined cycle-engine inhales oxygen from the air for about half of the flight, so it doesn't have to store the oxygen on board. That reduces the vehicles launch weight at launch, resulting in significant cost savings. At launch, the engine is empowered by specifically designed rockets strategically placed in a duct that captures air. Once the vehicle reaches twice the speed of sound, the rockets are turned off and the engines relies totally on the oxygen in the atmosphere to burn its fuel. When its speed increases to about 10 times the speed of sound, the engine converts to a conventional rocket powered system for the final push to orbit. "End Quote".

Statement: The mistake made here is that the vehicle is still essential being treated as an entirely physical system, remember, whatever we are trying to achieve to be successful it must from the onset be aimed at achieving Efficient Motion from "brakes off" to landing.

Statement: If an economically viably SSTO/RLV is the objective and Motion Efficiency the dominant control factor then, employment of a rocket

Below 100,000 feet cannot be the answer.

Statement No.13: While it is undoubtedly true that a rocket delivery system augmented by the entrainment of an air mass in the manner described will in effect mean a weight saving this in no way meets the requirements identified in, Statements 3, 5, 6.

Statement No.14: However, the air-breathing rocket so called does more than any other concept meets the criteria of Statement No.4 and the criticism of Statement No.8 very well.

Statement No.15: As a consequence of 13 & 14 this concept has the potential of beating any of the others, in terms of AVG's understanding that is.

Consider: The motion efficiency of any vehicle which is particularly critical at these Velocities is in the main determined by how efficiently the rate/velocity of thrust delivered in the ACTION half of the Vehicle's Motion System Cycle is matched by the RESULTANT velocity of the Vehicle. And, the rate of velocity of the Vehicle is the same as that of the velocity of the entrained aim mass entering the surrounding duct.

Consider: The so called air-breathing rocket in fact achieves a far more important gain than any weight saving consideration because of its compliance with Statement 4 & 8; entrainment of the air mass from the surrounding air. In actual affect, this is perfect, because what in fact this does is create a direct linking between the ACTION & REACTION halves of the Vehicles, Motion System Cycle. In effect the ACTION & REACTION halves of the Cycle are for the very first time in aviation/aeronautics history caused to PARALLEL each other. The interaction effect of which will be to balance out the difference between the rate of delivery of the entrained air mass with and the rate of delivery of the rockets thrust and in so doing dramatically improving propulsive effectiveness of the rocket upon the vehicle in a way that has never been achieved before. This is where the real gain is, consequently, imagine our puzzlement that having achieved this the rocket is switched off and ram jet operation takes over, why? The propulsive efficiency of a rocket is normally rubbish, however, entraining the air mass from the REACTION half of the Vehicle's, Motion System Cycle in this way, dramatically improves this and particularly at speeds beyond MACH 2.

Statement: Had the world's jet powered aircraft industry the sense to employ this principle of the tube entrainment system as the means of improving the propulsive efficiency of the pure jet instead of adopting the horrendously costly bypass, fan and variable cycle routes of development then, this Industry would be in a vastly better financial shape than it is today.

Statement: However, the entrainment concept is still to limited in its effect, because, to meet the SSTO/RLV requirements, the entrainment involving the use of a rocket in this way does not quite comply with the need set out in Statement No.4. Here, the end of the ACTION half of the Vehicle's motion cycle is linked with the end of its REACTION half in stead of between the end of the ACTION half and the start of the REACTION half. This means, there is absolutely no way a fully interactive motion gearing can be achieved between the rate of delivery of the rockets (very high) exit velocity with the Vehicles RESULTANT velocity especially from take off up to at least Mach 2 and this is extremely critical if an SSTO/RLV is ever to be achieved within the next decade.

Technology is neither the limiting or controlling factor in the solving of this task, remember, there is no such thing as a jet powered aircraft in terms of motion law, as there is no such thing as a rocket powered vehicle, they are both motion vehicles that are in their respective ways caused to fly.

And, it is efficient utilization of, Sir Isaac Newton's 3rd Law

Motion that is the critically determining factor in all motion flight, which is as it should be. The "key" is understanding that the relative importance between mass and motion completely changes above a certain velocity and depending upon the mass involved. Fail to understand this and get it wrong in your design and this will undoubtedly prove to be, extremely costly.

Consider, Kinetic Energy = half the Mass X the Velocity squared, and above Mach .87, in this kind of vehicle challenge understanding the significance of this relationship is critical.

Finally, we at AVG reject the description of the air-breathing rocket as an ejector system, this is not correct, you are in effect ejecting nothing. By entraining the surrounding air mass from around the Vehicle in motion you are in effect linking the two component halves of the Vehicles motion system cycle. In reality, you are in effect simply completing the connection between the ACTION and REACTION halves of the Vehicle's, Motion System Cycle. And, leaving the system in the way it does, is simple the completion of the cycle from which nothing is in fact being ejected in the ejection sense. The Motion Cycle of the vehicle is in fact being completed by this action. The exhaust from a motor car is more of an ejector in our understanding than is, that from the, so called, air-breathing rocket system.