Briggs Aerospace Technologies
 

HYT vs STS

The J2000 HYT will bring the spacecraft to the world the Space Shuttle was marketed as. 

HYT will bring a comfortable, spacious cabin environment for the crew, safe aspects of a design linked to a commercial airliner. The design is projected to be so economical in operation that it will compete with long distance surface postage per kilogram. HYT will be able to take-off and land at any international airport in the world, permitting easy access by users.

Leasing reduces the cost further due to the aspect of competition, and the 15 HYTs will enable a rapid expansion of space programs, resulting from the easier access to the stars.

Ballistic comparison HYT versus Space Shuttle

So how will HYT compare with the now retired Space Shuttle in ballistic flight? Probably the best demographic to demonstrate this - to the broadest amount of people - is to examine where both types transition to orbital velocity.

For the J2000 HYT, this is the height where it accelerates above the Neecenow airliner cruise speed and altitude, and the Space Shuttle rotates into an orbital altitude after the vertical ascent.

HYT will be at Mach 7.4 using hypersonic cruise engines, presumed to be Scramjets here, prior to firing booster engines with 250,000kgs of fuel, flying horizontally. Its wings produce lift, which also is a thrust component, saving fuel.  

The Space Shuttles transition altitude is much higher, 6 minutes after lift-off. It has no significant horizontal speed component of orbital velocity, still ascending in a near vertical attitude, so must still vector to an orbital attitude: at right angles to the Earth – if it was an aeroplane, it would be regarded as needing to go from a vertical climb to horizontal flight.

At this stage the STS was nearly on top of the Earth’s atmosphere - where there is virtually no drag - travelling at Mach 4.5. The Space Shuttles main tank with only 180,000kgs of fuel aboard still has to fuel acceleration to orbital speed, while continuing to loose energy to gravity during its pitch over manoeuvre into the correct attitude for orbit. One minute in the vertical loses nearly Mach 2 of speed to gravity (10 metres per second x sixty seconds equals 600 metres per second, the speed of sound at sea level is 330 metres per second).

The figures significantly favour HYT to meet or exceed performance expectations.

Gravity

HYT: Cancelled by lift from the wings, minute energy loss to induced drag.     

STS: 9.8 m/s deceleration towards Earth; velocity is lost to any positive (vertical) pitch which can only be overcome by thrust, increasing fuel usage and requirements to meet the same performance as an aerospaceplane.

Orbital Interception

HYT: On target – minor corrections to incline 

STS: Must vector against all forces - gravity, inertia, centre of gravity displacement, induced and parasite drag.

Centre of Gravity

HYT: Excellent control

STS: Large range – unstable = increased fuel burn and drag to restabilise

Manoeuvre

HYT 0.6G at Mach 7.4 reducing as speed increases Reduces drag 

STS: Vertical to horizontal 2-3G pull.  Energy and all vertical velocity lost in transition

Mass

HYT: Higher weight

STS: Lower weight

Speed

HYT: Mach 7.4+ (35% orbital velocity), horizontal (orbital incline); prior to main rocket firing -

STS: Mach 4.5+ vertical (21% of orbital velocity, however, on an incorrect vector - all speed lost to gravity) - acceleration to orbital velocity (speed horizontal to the Earth) required

Attitude

HYT: horizontal, poor climb performance, but enables easier acceleration to a faster velocity enabling a faster climb rate

STS: vertical = fast climb to orbital altitude but must overcome gravity and aerodynamic drag.

Induced drag

HYT: Reducing or constant with acceleration and reducing atmosphere; pitch over manoeuvre into zero G decreases induced drag.

STS: Pitching manoeuvre from vertical to horizontal (as well as turning onto the orbital incline) plus high lift wing, plus high drag tank (also producing induced drag)

Parasite drag

HYT: Low-drag ARFG based design

STS: huge frontal area (STS and fuel tank) plus poor streamlining (blunt ended, large fuel-tank, main and BTO engine areas of significant drag)

Inertia

HYT: Orbital attitude - centrifugal + gravity = increased momentum

STS: Vertical, inertia is used to ascend with losses to gravity, vectored momentum

Stability 

HYT: Natural aerodynamic and inertia 

STS: Unstable - fuel burnt to stabilise

Upgrades 

HYT: Connected to the ARFG airliner. Ongoing efficiency increases to scramjets = increased thrust, reliability and lower fuel burn

STS: Minimal development over 30 year life, retired 2010

Aerodynamic

HYT: Shock wave riding design

STS: designed as a glider + blunt, high-drag fuel tank

Fuel load for rocket engine(s); orbital transition: T+ 6 minutes

HYT 250,000kgs   

STS: 185,000kgs

Drag loss demo

The SRBs continue upwards for a minute after separation, ascending 21km.

While this may sound incredible, the initial speed of the SRBs is Mach 4.5: a kilometre and a half per second, demonstrating the incredible loss to speed to drag and gravity.

Speed loss to gravity = Mach 2

Speed loss to drag=Mach 2.5

The main component of the speed (about Mach 2.5 in the minute, about 1.25G in deceleration terms) is lost to drag - even in the rarefied atmosphere of that altitude and despite residual thrust form the SRB. This demonstrates the amount of drag which rockets must ordinarily overcome with thrust.

One minute’s gravity will accelerate (or decelerate) an object to about 2000km/hr: or about twice the speed of sound (Mach 2).

J2000 HYT does not accelerate in the vertical, it accelerate in the horizontal. Its low drag design means very little speed, and thereby fuel, is lost to drag.

Evolution

HYT’s connection to the ARFG is fantastic for the future, because engineers will find efficiency gains to offer upgraded engines to airlines; feeding into HYT, and visa-versa.

Airlines engineers servicing Neecenow, from all over the world, will also find better ways of making engines easier to maintain and more efficient. These will result in reduced costs, greater reliability, and increasing mission rates to HYT operations. These engineers may come from less typical back-grounds whom would ordinarily not be employed due to the typically individual government-run space industry.

The Hole cards

Above the demonstrated figures here showing HYT’s ability are these magic and very real excluded points potentially taking HYTs performance to whole new levels, or be used as redundancy to attain performances, if lost via engineering shortfalls.

Unleashing the beast

The cruise speed of the ARFG Neecenow airliner is set for practical reasons at Mach 7.4. To give a rounded estimate, this is speed noted as the J2000 transition speed comparison.

However, it isn’t yet known how fast a Scramjet can go. The speed record for Scramjets engines is currently almost Mach 10, with estimates of top speeds possible between Mach 10 and Mach 25. The actual speeds attainable of early Scramjets are likely to be the lower of the two figures, with later, developed versions nudging the latter figure of Mach 25.

Although higher speeds using Scramjets will use more fuel to attain, these power plants use far less fuel than rocket counterparts for the same acceleration, ultimately reducing:

  • The fuel requirements for the rocket engine
  • The size of the rocket engine required
  • The maintenance and turnaround times and costs of the rocket engine
  • Mission turnaround times and cost will lower

The Sanger Clause

A rocket must desperately escape Earth’s atmosphere as soon as possible –vertically- due to the amount of drag produced, and the fuel consumption to overcome the maximum effect of the Earth’s gravity.

The super-couple whom originally conceived hypersonic aircraft, Dr Eugen Sanger and Dr Irene Bredt, theorised to improve range a hypersonic aircraft could skip across the top of Earth’s atmosphere to attain great range. Another similar technique known as Dynamic soaring was inspired by maritime birds which fly for thousands of kilometres by manoeuvres conserving momentum, and is a commonplace among advanced glider pilots.

These techniques can be coupled to accelerate HYT to orbital or escape velocities using less fuel. The energy attained by accelerating with gravity and the increasing pressure pushing the aircraft back upwards to a higher altitude and speed than would be attained by trying to climb under power. To explain this effect by comparison is similar to skimming a stone across water, or tic-tacking a skateboard, a similar technique once used to save fuel on both Concorde and Lockheed SR-71 flights.

A faster moving object loses a lower percentage speed to gravity while covering a much larger distance, reducing the influence of G. Such a descent enables Scramjet engines to breathe and operate for longer periods, since the period in the atmosphere is longer. The final velocity attained is higher, meaning it is under the effects of gravity for a shorter time when escaping the atmosphere. The advantages are reduced required thrust to accelerate or maintain orbital speed.

Dynamic manoeuvres also reduce the amount of fuel required to attain orbital velocity and altitude, increasing payload performance capability.

The Wavesoarer

Among the legends of high speed flight is a technique known as shockwave riding or compression lift. This comes about by designing the aircraft to produce lift from the hyper-compressed shaft of air split by the wings and fuselage as the aircraft moves through the air at super and hypersonic speed.

By using this area of flow to produce lift dramatically reduces the amount of power involved to fly at speed. This has been convincingly demonstrated on the XB-70 Valkyrie test aircraft 50 years ago. This effect can literally throw or slingshot the HYT out into orbit once at a certain speed.

General comparison

A general look at HYT in comparison to rockets and the Space Shuttles (STS) demonstrates performance qualities.

Safety:

   HYT                   STS                      Rockets

 Excellent           High risk                  High risk

Prior Space launch transports have lacked any protocols or safety standards. The disposability and cost factors influence ultimate safety - or lack thereof – of a rocket. Why should something be built to last if only used once?

The problems of the Space Shuttle programme were well known, from intense buffeting and vibration shaking heat shield tiles off during launch - a factor never solved - and returns often delayed or diverted due to weather. 

Shuttle flights were flown by computer: uncommon even today in commercial aviation for many good reasons. Few changes were implemented over the life of the STS programme, again something which would not happen in commercial aviation, with its constant flow of airworthiness directives.

J2000 HYT brings a new level of safety into spaceflight, designed and to be built from a production commercial airliner design that will have thousands of hours in testing and development of its superstructure, to meet stringent FAA and ICAO guidelines. This will be reinforced by the Neecenow airliners flying tens of thousands of flying hours every year, serviced by talented engineers from all over the world.

Payload                 

   HYT                  STS                      Rockets

110 tonnes         30 tonnes        up to 130 tonnes (Saturn V)

J2000’s 110 tonne payload capability is close to Von Braun’s Saturn V (record) capability of 130 tonnes. The difference is that as well as HYT costing much less than a rocket of this lifting capability, the HYT can return to Earth and return to orbit within a few days. A rocket was and is an expensive one shot deal, it’s payload to orbit inevitably includes deadly space debris.

The Space Shuttle had a good payload though at 30 tonnes it would always have trouble reducing the costs per kilo into orbit. Much of the mission performance of “what could have been” was lost in delays from many different areas of the programme, cost increases and budget cuts. 

HYT’s payload and cargo bay allows for large objects to be carried into Space, meaning less sub-assembly is required in building facilities in Space. This in turn requires fewer missions, reducing costs, and time and risk to astronauts assembling components together. It creates opportunities to build larger facilities, to design at larger scales, augmented also by the high flight frequency and the low cost of spaceflights. 

Mission frequency will lift with development of the HYT and increase safety of the whole fleet.

Orbits:

       HYT                           STS                         Rockets

Any orbital direction     Limited options          Limited options

Another big plus with the J2000 is the ability to attain any orbit with greater ease. Traditionally rockets find it difficult to attain orbit against the rotation of the Earth due to the speed lost accelerating to the higher speed required. 

By basing the orbit from a high-speed level flight launch from the Earth’s atmosphere, this aspect is eliminated.

Stability

    HYT                    STS                     Rockets

   Stable                 Unstable                Unstable

Rockets and STS have rapidly changing centre of gravities, non-existent streamlining and relatively increasing thrust from the rear, increasing drag. The latter is like balancing a pole on your finger - a lot of effort is required to keep it still: in rocketry this effort is burnt fuel, reducing mission altitude and payload.

The Space Shuttle was also unstable, its aerodynamic surfaces offering little stability. Any attitude other than pure vertical places high aerodynamic drag loads upon rockets, having large frontal areas. Although this is not so important once altitude is reached, at lower altitudes fuel burn is high from higher specific impulse at sea level in comparison to the vacuum of space. 

HYT is flown as an aircraft for a high percentage of the transition to orbital velocity and altitude. To maintain effective control in aircraft, the centre of gravity is critical and the Neecenow based shock-wave riding design can manage this, saving fuel, reducing drag, flying a more precise course with the highest safety to the crew and payload.

Living quarters:

     HYT                              STS                       Rockets

   Spacious                        Cramped                Seats only

The Space Shuttle introduced a work environment in Space unlike any before it. This environment reflected a workplace, rather than a confined capsule. It had a large, spacious cabin with areas of privacy such as toilet and shower facilities. 

The main part of the success of the Space Shuttle was its crew’s ability to function optimally as a team and as individuals due to the better and bigger working environment, no longer cramped up like animals in a can, they were space travellers. 

With HYT, this type of living space is improved and coupled with safety of airline-based engineering servicing essential to long term interests of commercial Space activities. Astronauts will have their own compartment areas allowing retreat and recharge to perform at their highest level. 

The item most specific to mission success is its crew. It’s easier to do a good job in a good environment. Astronauts face long periods of wakefulness, perception problems and other human difficulties known as human performance factors and limitations from zero G conditions. Sleep deprivation is equivalent to being drunk. Space capsules have no room to retreat or have privacy; there is stress and fatigue increasing risks of errors. 

Even best friends find it hard to get along when stuck together for days; Space missions last for weeks in an environment of boredom and extreme competition. Much of the mission effectiveness can be lost to human performance factors.

Maintenance

  HYT                      STS                           Rocket

Excellent                 Poor                         Disposable

15 J2000’s operated by 3-6 major airlines, derived from the ARFG Neecenow, to be operated by most major airlines worldwide = large engineering pool, large numbers of aircraft to derive any potential faults. 

This aspect also produces a larger supply of spare parts, making maintenance cheaper plus easy access to parts and spares, reducing turnaround times. An airworthiness direct program would exist for the engines, increasing the life of the main engines while reducing costs.

Mission turnaround is designed to be fast and inexpensive; the only slow down would be the rocket motor which is designed to be easily and quickly replaced if required.

STS had only several hundred elite engineers, servicing a limited design on a limited budget. The Space Shuttle engineers had little say in mission or of servicing, leading to failures. Parts took a long time to access and fit, had high cost and took months to turn around, increasing relative costs, with missions cancelled. Military space-flights took precedent over civil payloads.

Conventional rockets are disposable meaning less effort is placed upon the safety of the crew, the payload and the mission: the only time they are properly is on the rockets one and only flight: new cars have faults, despite being infinitely less complex than a rocket and on large production lines.       

Reusability

    HYT                  STS                 Rocket

Completely            Good               Disposable

Reusability means ultimately costs are lower. Rocket engines are expensive due to the forces - such as heat and pressure - involved. Precious materials are used in the construction, which in disposable rockets only pushes up the price due to loss of the materials taking place. 

Disposable rockets contribute to thousands of tonnes of space junk in orbit, creating a hazard to future missions and space hardware. There is also a lot less available data to engineers, in terms of post-flight analysis of components, to assist in development: ground testing does not produce the results of actual flight testing due to the temperature and dynamic changes involved.

The Space Shuttle attempted to address these issues, with only the external tank being disposed of. Although recycling the Orbiter and SRB boosters was not as economically viable as hoped, its contribution to development and reducing material dumped in orbit has been undervalued.

J2000 HYT will be completely reusable, enable full development of components, and, in conjunction with the Varulkarie, ensure clean and safer skies.

Peak G (acceleration)

    HYT               STS            Rocket

    1.5G               3G+          8G+ (Saturn V)

The acceleration is the amount of additional weight a person feels due to the inertia occurring due to a change of direction. In the early days of rocketry, G-forces of above 8G were experienced, and it was only due to the prone position of the astronauts they did not black out. Flight was almost completely automated as the astronauts, as fit as they were, could not be expected to undertake much of a workload under the acceleration involved.

J2000s peak acceleration takes it from the era of danger, expense and risk into a new age of safe, low cost, dependable and capable spaceflight. The acceleration of a J2000 will not be significant. HYT will have 1.5G at peak, allowing virtually anyone able to fly into space. The progress of spaceflight is to make it a mundane, uneventful trip.

Greater forces exponentially affect the amount of reinforcement required in structure to allow a safe trip, leading to weight increases, reducing payload and increasing fuel burn. Rockets are limited to a single shot and can duly be under-engineered, since longer life products must cope with continued stresses over time.

G-forces also affect payload which must be built to be able to withstand the journey, increasing costs. Computers and precision equipment are reduced in finesse by requirements to cope with higher G.

By reducing the G-forces experience on the HYT, it reduces the loading on the structure, making the chance of failures, which affect the entire aerospaceplane (including electrics, structure and mechanics) remote.


 
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