MLAS Test:

The Max Launch Abort System (MLAS) is an evolution of two of the original three LAS concepts studied by Constellation. The MLAS concept combines the boost protection cover of the service module mounted escape system with the command module mounted motors.

MLAS study was kicked off back in June, 2007 – with a roadmap planned out until 2009. The project has been run from the NASA’s Exploration Systems Mission Directorate (ESMD) under special managerial funding, separate from Constellation funds. NASA’s Langley center has been leading the design of the system.

Grown out of the hand drawn sketch by Mike Griffin, dated March 22, 2006, the MLAS concept has been gaining momentum as a solution to unspecified issues relating to the traditional tower abort system.

The design of MLAS has changed several times during its development, gaining fins for stability during later cycles, becoming more in line with another hand drawn sketch by former Constellation head Scott “Doc” Horowitz – as seen in one of two MLAS presentations acquired by L2 – over a year after Mr Griffin’s conceptual design.

The final version of the MLAS flight test vehicle weighs in at over 45,000 lbs and is over 33 feet tall.

The ‘bullet’ aerodynamic cover houses four Mk 70 Terrier solid motors that are used to power the abort. Two orientation parachutes are attached to the top of the fairing to re-orient the vehicle with the blunt heat shield into the wind and to aid in fairing separation.

The pad abort test proper began seven seconds after burnout of the solid motors, as the vehicle rose into the Virginia morning sky at 6:25am local time.

Witnesses of the launch claim the vehicle rose on a stable flight path, before reorientation and further stabilization, followed by crew module simulator separation from the MLAS fairing, and parachute recovery of the crew module simulator. All events appear to have been ably completed without issue.

“The test demonstrated a number of things: the unpowered flight of the MLAS along a stable trajectory; reorientation and stabilization of the MLAS; separation of the crew module simulator from the abort motors; and stabilization and parachute recovery of the crew module simulator,” wrote NASA PAO’s Rebecca Powell.

“An important objective of the test was to provide the workforce of NASA’s Engineering and Safety Center, or NESC, with experience in flight testing a spacecraft concept.”

Other tests are planned for MLAS, including a high altitude abort, which will involve the fairing being released immediately after abort is called to allow the Command Module Reaction Control System (RCS) to stabilize the vehicle for entry.

If Ares I survives the ongoing reviews, and MLAS is chosen as a successor to the current LAS, a four piece fiberglass fairing will cover the Command Module to create a flush edge on the Ares I launcher.

See original article outlining MLAS in 2007 – six months before any other media noted the system’s existence:
http://www.nasaspaceflight.com/2007/12/mlas-the-alternative-orion-launch-abort-system-gains-momentum/

Ares I-X:

The four segment test vehicle is scheduled to begin stacking operations on its Mobile Launch Platform inside High Bay 3 of the VAB on Wednesday evening, following the arrival of the aft booster section into High Bay 4 earlier this morning.

“The Aft Booster will be brought over to HB4 this morning after peak traffic. Will start stacking ops (clears) at approx 1630hrs tonight,” noted Wednesday processing information on L2. “Ares I-X (VAB HB-3/4) (RPSF) (Pad-B) RPSF: Transport Aft Booster to VAB is scheduled for today.

“VAB HB-4: Forward Assembly/Interstage mate to 5th Segment Simulator (5SS) was completed yesterday. Post ops in work. DFI Config2 GSE interconnecting cable mates in work. Stack-1 Modal test pre-ops continue.

“US-7: Install 2 Bus Couplers and 1 Temperature Sensor in work. US-6: Install upper stage camera and video test in work.

“VAB HB-3: Receive Aft Booster and mate to MLP is scheduled for today.”

Currently scheduled for a September 17 launch, it is likely the additional requirements of “loads analysis” on the vehicle during the upcoming stacking operations will threaten to push the launch date into October – which has been expected by engineers as of last year.

The reason for the additional testing on the stack relates to threats to the vehicle’s Flight Termination System (FTS) during periods of Thrust Oscillation as the vehicle launches uphill.

However, there has also been an undocumented note of concern relating to FTS risk associated with vibrations at Max-Q – which would be more serious, given the earlier phase of ascent the vehicle will pass through the period of maximum aerodynamic pressure, and thus a potential constraint to gaining the required range waiver from the US Air Force.

“USS (Upper Stage Simulator): Continue with Aft Booster stacking ops but we still have outstanding loads analysis results pending. We will create a checkpoint prior to the stacking of Stack-1,” added associated notes on Wednesday.

“If analysis results are good we will then proceed with the remainder of stacking. This will prevent a situation of a possible de-stack to correct any issues and avoid future delays.”

Ares I-X engineers will use the data gained from the periodic testing on the vehicle’s integrity during stacking operations to hopefully eliminate such concerns.

L2 members: Documentation – from which the above article has quoted snippets – is available in full in the related L2 sections, now over 4000 gbs in size.

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JDTV:

The first test of the giant parachutes that will be tasked with easing Ares I’s five segment Solid Rocket Motor First Stage’s return to earth for splashdown in the Atlantic didn’t go fully to plan, with damage sustained to the JDTV – which mimics the Ares I First Stage, if not by appearance – during its debut drop test last summer.

An Integrated Product Team (IPT) conducted a design and analysis review of modifications to the JDTV, which resulted an increase to the strength of the buckled components, following its hard landing, and the inclusion of break-away fins – which were re-manufactured prior to the upcoming test.

This should avoid future damage to the reusable test vehicle, which is deployed out of the back of a US Air Force C-17 transport on an extraction pallet.

Teams successfully completed the tow tests of the new C-17 air drop extraction (pallet) system to be used on the upcoming JDTV parachute drop tests. A new extraction system was required since the standard extraction system utilized by the Air Force has a 60,000-lb extraction limit.

“The new extraction system uses Vectran rope, along with modified standard Army 15-ft drogue, and 28-ft extraction parachutes that have been structurally reinforced with Kevlar radials,” noted Ares Program information.

“The test consisted of towing the modified drogue and extraction chutes with the Vectran rope behind a C-17. The test objectives were to measure and record the tow forces of the parachutes at various air speeds and parachute reefing positions and visually record their proper deployment.”

The drop will take place at 10am on February 26 – weather permitting – at the US Army Yuma Proving Ground, located close to the Arizona-California border, which has been the site for most of the drop tests for the Constellation program.

Last summer, the Orion Parachute Test Vehicle (PTV) – a truncated looking Orion – suffered a failure, ripping off its parachutes and crashing to the ground, after it became inverted following extraction from a C-17 aircraft.

The vehicle is now scrapped, located in the “boneyard” of the Army base.

In 2007, the third Parachute Drop Test (PDT) – which was testing a pilot parachute for the Constellation program – resulted in the Drop Test Vehicle (DTV) being destroyed.

The test vehicle hit the ground with such velocity, special excavation equipment was required to recover the nose of the DTV – which was buried 30 feet below the surface. All other tests have been deemed a success.

MLAS (Max Launch Abort System):

Specially funded outside of the Constellation program, under the leadership of former Constellation head Scott Horowitz and NASA Engineering and Safety Center (NESC), the MLAS is confirmed to be just a month away from an opening salvo of tests.

First revealed by NASASpaceflight.com last year, several presentations on L2 outline the concept that appears to have grown out of the LAS trade studies in 2007.

During that trade study, three candidates were evaluated, namely the Multiple External (x4) Service Module (SM) Abort Motor concept, the Crew Module Strap On Motors (x4) concept, and the In-Line Tandem Tractor (Tower) concept – with the latter then baselined into Ares I/Orion design.

The trade study presentation – also on L2 – shows a ‘hand drawn sketch’ by former NASA administrator Mike Griffin, dated March 22, 2006, that is believed to be the origin of MLAS.

The “alternative” Launch Abort System was originally set to carry out a pad abort test in September, 2008. However, concerns the system is far too heavy for Ares I, and the continued push to baseline the traditional “tower’ LAS, initially led to rumors the project had been cancelled.

Although never specifically noted as anything other than an alternative “fall back position” system, it is possible MLAS is part of a backup plan for a Human Rated Ares V, given initial studies into man-rating the huge vehicle note it would be impossible to stack with the current LAS tower, due to height restrictions regarding vehicle integration inside the Vehicle Assembly Building (VAB).

With MLAS on top of Ares V, the vehicle could be stacked within current restrictions. A Human Rated Ares V would only become a reality if Ares I development was ceased, and the alternative options of EELV and Direct’s Jupiter vehicles failed to win approval under such a scenario.

For now, the Constellation program are only classing MLAS as an “alternative” to the LAS tower, even though it would be near unthinkable to make such a large change to Ares I at this stage of development.

“Like the leading NASA launch abort concept, MLAS offers a safe, reliable method of pulling the spacecraft capsule and crew out of danger in the event of an emergency on the launch pad or during the climb to Earth orbit,” noted NASA in releasing the date of the pad abort test.

“A NASA team is preparing to demonstrate an alternate escape system design to explore different technological approaches. Named after Maxime (Max) Faget, a Mercury-era pioneer, the Max Launch Abort System (MLAS) concept will be validated by conducting an unmanned pad-abort test in March at NASA’s Wallops Flight Facility, Wallops Island, Va.”

The dates listed involve a parachute drop test of the MLAS on March 5, followed by the pad abort test on March 27.

Representatives from the Sounding Rockets Program Office and NASA Sounding Rocket Operations Contract, (NSROC), have provided technical support associated with the solid rocket motor systems used by MLAS. NSROC also play a major role in vehicle hardware and mechanical GSE (Ground Support Equipment) fabrication.

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