Starship Orbital Test Flight - 4/20 Launch

[ÆCIII]

What amazed me was the apparent sheer weight of the booster full of fuel on liftoff, and the slow initial rate of ascent at liftoff - and the actual hesitation before liftoff.

Guess they didn't call it "Super-Heavy" for no reason...

With how the Raptors have been performing in smaller numbers on other tests, I thought 33 of them might get it off the pad at least slightly faster. But again three Raptors were apparently out even at launch, and more of them were out soon after liftoff in the ascent.

I was also impressed at how strong the stack was, and how it stayed together performing with all that fuel on board. I wonder if this test has set any record for how much fuel, CH2 and LOX, was on board any single rocket booster or vehicle at liftoff.

When I get the chance, I might look at some old Saturn V footage to compare how fast each vehicle rose off the pad at liftoff.

- ÆCIII

 

[hridge2020]

But did you see the 25ft hole it made and the mini hurricane it created that broke all the youtube camera gear....I'm pretty sure debris was the cause of some of the motor failures on launch. That thing was insane.

Yep. Who Allowed That car equipment so close to pad..
I guess no one remembers the Delta II launch pad disaster.

 

[Kahpernicus]

The lot across the the street is private. So it's pretty much at their own risk but probably worth it to them.

 

[JBee]

The cars were allowed to intentionally park there for all the camera gear that was mounted on them from all the youtubers. They didn’t really expect damage from a successful launch as such, but knew it would be wiped out if it exploded on the pad.

 

[JBee]

What amazed me was the apparent sheer weight of the booster full of fuel on liftoff, and the slow initial rate of ascent at liftoff - and the actual hesitation before liftoff.

With how the Raptors have been performing in smaller numbers on other tests, I thought 33 of them might get it off the pad at least slightly faster. But again three Raptors were apparently out even at launch, and more of them were out soon after liftoff in the ascent.

I was also impressed at how strong the stack was, and how it stayed together performing with all that fuel on board. I wonder if this test has set any record for how much fuel, CH2 and LOX, was on board any single rocket booster or vehicle at liftoff.

When I get the chance, I might look at some old Saturn V footage to compare how fast each vehicle rose off the pad at liftoff.

- ÆCIII

Much slower than a Falcon 9 or Shuttle, but not too dissimilar to Saturn 5. I'm pretty sure they knew the pad wasn't as secure as they wanted, so they took it slow off the line, and veered away from the tower pretty fast after launch.

Those Raptors are extremely powerful, I really don't get how they thought their special reinforced concrete would hold up without a water deluge system. The slow start probably just made it worse, in that it gave more time for debris to ricochet back to the rocket. It rained sand 6 miles away just from the launch. There's also something solid that launches into the air whilst ins on the pad.

If you watch the launch, pay attention to the flare ups an fires just above the engines. I think that was one of the two hydraulic pumps that went, and I think that's why they ended up with control issues, and needing differential thrust to compensate, which derates total available thrust, and together with the failed raptors, led to not enough velocity to reach seperation altitude with the fuel they had left.

I haven't heard anyone say that yet, but I strongly suspect that was the sequence of events that led to the failed roll for seperation and self destruct.

I hope not, but It might be 6 months before they get Stage 0 good enough for the next one. Some tanks were damaged too.

 

[ÆCIII]

Yep. Who Allowed That car equipment so close to pad..
I guess no one remembers the Delta II launch pad disaster.


. . .

Yes, so funny in the Delta II launch, how they call an unexpected freaking' explosion an "anomaly". Typical media heads when confronted with truth and reality right in front of them.

Just say "The vehicle booster has just exploded..." already!
But nooo... Cannot accept ... Cannot cope... Media heads in typical form. Of course they could say they were looking at telemetry data and not video - even though that's highly unlikely, but anyway ...

They also could have called it a "Rapid Unscheduled Disassembly", but Elon hadn't taught them that more truthful descriptive phrase yet ...

But lots of lessons learned and data collected in this Super Heavy and Starship test - which was actually the primary objective.

- ÆCIII

 

[Kahpernicus]

The thing about the liftoff is that, they did a staggered engine start up, so it wasn't until a few seconds in that they had enough thrust to start moving.

 

[JBee]

Woopsies...sorry did I do that?

 

[Crissa]

imagine the forces on the rocket while it was spiraling - and it didn't break apart. wow.

It's supposedly supposed to do the flip and separate as a single motion, instead of two, like Falcon 9 does.

Yes, so funny in the Delta II launch, how they call an unexpected freaking' explosion an "anomaly". Typical media heads when confronted with truth and reality right in front of them.

Just say "The vehicle booster has just exploded..." already!
But nooo... Cannot accept ... Cannot cope... Media heads in typical form. Of course they could say they were looking at telemetry data and not video - even though that's highly unlikely, but anyway ...

They also could have called it a "Rapid Unscheduled Disassembly", but Elon hadn't taught them that more truthful descriptive phrase yet ...

It's an anomaly, because it wasn't supposed to happen. The explosions are usually just the flight termination, as in, someone pushed a button to make it go boom.

For instance, the space shuttles also didn't explode. The Challenger was destroyed in an explosion, but it was the main fuel tank - which is a different vehicle than the shuttle - that exploded. The Discovery imploded, it didn't explode.

Elon didn't coin 'rapid unscheduled dismantling' but it's just as much a euphemism as any other.

Starship Super Heavy was exploded, it didn't explode without being told to do so. The Falcon 9s which have exploded were not told to do so, but only two of the several was the explosion the end of the mission. Exploding after you hit the pad is crashing, then exploding, versus exploding, and not landing.

If you want to be all pedantic.

-Crissa

Yeah, yeah, this is why I went to University, to argue pedantically about aerospace engineering.
https://en.wikipedia.org/wiki/GPS_IIR-1

 

[hridge2020]

Ka-Boom

Flight Termination System

Several types of flight termination actions are possible; however, from range safety perspective, explosive charges breaking up the vehicle is normally the preferred method.

TS
Requirements for a flight termination system (FTS) are defined in detail by Range Commanders Council Range Safety Group, 2010. The following summarizes key features of an FTS. An FTS must:
1.
control vehicles experiencing failure or degraded performance that can lead to a public safety hazard by eliminating thrust, lift, yaw for all vehicle stages;
2.
produce a small number of pieces, all of which are unstable and impact within a small footprint;
3.
control disposition of hazardous materials (burning propellant, toxic materials, radioactive materials, ordnance, etc.);
4.
be supportable during assembly, test, prelaunch, launch and flight operations at launch range; and
5.
demonstrate high reliability and probability of survivability of operating environments with adequate reserve margins.
The basic components of an FTS system are:
1.
Flight Termination Receiver;
2.
Antenna System;
3.
Independent Battery Source;
4.
Safety Lockouts: Safe and Arm devices, timers, etc.;
5.
Termination devices (cutting charges and other explosives, fuel valves, ignition cut-off relays, etc.);
6.
FTS control and monitoring devices.
Figure 4.1.7 depicts a typical flight safety system, the connections to key FTS components, and the required communications channels for the system.

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FIGURE 4.1.7. Typical flight safety system with FTS.
(Range Commanders Council Range Safety Group, 2010)
Once a vehicle is airborne, the range safety system and the FTS, in particular, are the only tools available to assure public safety in the event of a failure. Range Commanders Council Range Safety Group, 2010, is one of the most definitive guides to FTS requirements. Consequently, Figure 4.1.8 is given as a guide to the reader who desires to pursue an understanding of these systems in greater depth. Chapter 2 of Range Commanders Council Range Safety Group, 2010, characterizes a practice operated by US government ranges to allow range users to demonstrate that they can meet the safety requirements for the FTS systems without complying with one or more of the detailed requirements.

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FIGURE 4.1.8. Structure of RCC 319.
(Range Commanders Council Range Safety Group, 2010)
Chapter 3 of the RCC 319 standard details performance requirements at the component, subsystem and system level. Chapter 6 focuses on the design considerations for the ground support and range safety system monitoring equipment. Chapter 7 discusses how analyses may be employed to reduce the required testing and to demonstrate compliance with the performance requirements. Chapters 4 and 5 detail the testing requirements at the component, subsystem and system level intended to produce a highly reliable system in operation. Finally, Chapter 8 characterizes the required trail of documentation of tests and analyses to assure traceability of the implementation of requirements. Cited chapters refer to Range Commanders Council Range Safety Group, 2010.

A significant emphasis of this document is placed on assuring that the system will function as intended with a high degree of reliability. To that end, Range Commanders Council Range Safety Group, 2010, details specifications for several types of tests of the system and its components:
•
Qualification Testing is used to provide confidence that FTS and components can withstand operational environment and have adequate margins.
•
Acceptance Testing is used to prove workmanship. It increases the confidence that production units are as reliable as those that passed the qualification testing.
•
Certification Testing is typically performed on critical components after acceptance testing, as close to launch day as possible. Certification testing is typically performed on Flight Termination Receivers and Safe and Arm devices.
•
Assembly and Checkout tests are usually performed within 30 days of launch to detect a faulty component that may have developed problems since its last check. These tests are designed to provide end-to-end testing, as well as calibration of telemetry (TM) channels.
•
Prelaunch tests are final checks prior to launch on components such as Flight Termination Receiver tone checks, FTS battery, Safe and Arm devices.
The functionality of systems involving a Flight Safety Officer and autonomous systems is similar. Vehicle malfunctions must be detected and disposal of hazardous materials from the malfunctioning vehicle must be directed to impact safely away from people and high value assets.

An airborne Autonomous Flight Termination System (AFTS) eliminates the need for Flight Termination Receivers and Antenna Systems. The airborne AFTS adds the need for on-board processing and additional on-board sources of state vector information, such as GPS or inertial navigation system (INS) and associated hardware and software. Although AFTS have been used for a number of years and there is growing acceptance of their usage, they have not yet received total acceptance from the range safety communities. While an AFTS offers significant advantages in decreasing required support sensors, providing flexibility in launch locations and more responsive termination of an errant vehicle, there remain concerns which are currently being worked:
1.
Loss of tracking resulting in an AFTS action.
2.
Integrity of tracking data (clearly defining required actions when one or more sources are lost).
3.
Managing software single point failures.
4.
Managing potential common cause failures.
5.
Providing adequate assurance that conditions warranting vehicle destruct can be detected.
6.
Encompassing the range of flight termination rules currently employed at all ranges.
7.
Meeting the weight and volume constraints for additional hardware on missile and launch vehicle systems.
Several types of flight termination actions are possible; however, from range safety perspective, explosive charges breaking up the vehicle is normally the preferred method. The following is a brief summary of other methods that have been employed:
1.
Solid rocket motors may be equipped with thrust termination ports on the forward portion of the stage. Removing these ports nullifies the thrust of the stage. However, this type of flight termination may result in the impact of a stage containing substantial amounts of propellant with the potential for a large explosion.
2.
Liquid propellant rocket motors may be equipped with propellant and oxidizer shut-off valves. Closure of these valves causes the rocket motors to cease thrusting. The impact of the non-thrusting stage may cause the two tanks to rupture and produce an explosion.
3.
Vehicles with aerodynamic control surfaces may be caused to pitch into the ground or tumble by appropriate commands to these control surfaces.
Recently, in anticipation of increased flight of reusable launch vehicles (RLVs), there have been attempts to examine the applicability of other technologies, such as those employed for unmanned aerial vehicles (UAV) to launch vehicles (Fudge et al., 2003). Important concepts that have been considered include the possibility of flight-safing a vehicle and the possibility of vehicle recovery. Flight-safing a vehicle is a potential strategy for non-crewed vehicles capable of sustained powered flight within the atmosphere. When a vehicle is capable of redirection and sustained powered flight, this flight-safing requires controlled flight to a safe region. When feasible, the vehicle would then be directed to land. Otherwise, redirection to a safe way point would allow the vehicle to return to Earth safely. Vehicle recovery systems require the termination of powered flight followed by a “soft” landing, such as re-entry employing a landing system composed of parachutes to reduce the impact velocity and airbags to dampen the effect of the impact on the vehicle.

 

[CyberGus]

The explosions are usually just the flight termination, as in, someone pushed a button to make it go boom.

 

[Sirfun]

But did you see the 25ft hole it made and the mini hurricane it created that broke all the youtube camera gear....I'm pretty sure debris was the cause of some of the motor failures on launch. That thing was insane.

Wow, those Palm trees ae awesome!

 

[Kahpernicus]

They should make the flame diverter and mount out of palm trees.

 

[Alan]

I read that it’s latched down for the first 6 seconds while it does system checks. Then unlatches and throttles up.

 

[hridge2020]

[/QUOTE]


Great Job SpaceX, for launching your rocket.
Slow moving like the other heavy Rockets, Saturn 5, Artemis and Delta IV....

One other thing, no payload was in the first stage.. I'm sure adjustments and other calculations will be performed.

suggestion for what's left of your launch pad.

Since you developed your heat tiles for the Starship, you might what to test then for the top surface of your launch pad, plus rocket flames/smoke diverter. (of course make the heat tiles, larger)