Inherent Issues and Reasonable Response

https://www.yahoo.com/finance/news/house-republicans-just-launched-political-232200411.html

From the article....

3. Given the two recent failures of the Falcon 9, will the Air Force add more weight to mission assurance and schedule reliability vs. price in their future launch service procurements? If not please explain.

First off.... let me start out by saying that the investigation is still underway and no one knows for certain what happened to cause the Falcon rocket to explode on the pad during fueling operations on the pad at Cape Canaveral as of yet.

However, what we do know is that it did explode. Preliminary investigation reports indicate that it was a massive rupture of a Ghe vessel in the second stage LOX tank on the vehicle. Space Ex has been quick to point out that this is NOT the same issue that caused the spectacular mid air explosion on the first Falcon loss less than a year ago. At best, this is a partial truth. At worst, we may soon find that it has an identical cause in the very near future.

Having been personally involved in similar accident investigations in the past, I can say that the whole process of building a fault tree of possible causes and carefully and painstakingly running every possible cause to ground is a slow and painstaking process; especially when much of the evidence is no longer existing due to the inherent dangers that come with using a perfect oxidizer. LOX is Liquid Oxygen and it is the perfect oxidizer of which I am speaking.

LOX is necessary on rocket engines flying out of the earth's atmosphere for a couple of reasons, the main one being that all combustion requires oxygen to support it and once a vehicle is it out of the earth's atmosphere it cannot burn the oxygen in the surrounding atmosphere because there is none. Therefore, there must by an oxidizer on board and LOX is the most efficient oxidizer known to man. Since rocket engines are all about efficiency; ie.... weight to lift capacity on very narrow margins of failure.... LOX is a necessary evil when it comes to launching vehicles out of the earth's atmosphere.

As I have discussed before, the dangers inherent in using LOX are numerous and manifold in nature. It is a cryogen, operating at -297 degrees fahrenheit in it's liquid or condensed version. Exposed to anything above this temperature it will begin to boil with rapid explosive expansion on the order of 861-1 as it changes from a liquid to a gas. LOX is intolerant of hydrocarbons; such that even small traces of almost all known lubricants can cause instantaneous ignition on contact with LOX under almost any pressure at all.

Add just these two inherent conditions alone and you begin to see the difficulty in working with LOX. Since materials naturally tend to contract and shrink as temperatures drop close tolerances on rotating parts such as pumps needed to move LOX become problematic to lubricate effectively. Add in pressures often in the thousands of PSIG necessary to feed and sustain a rocket engine and the problems become infinitely greater.

LOX itself is inflammable. However, being the perfect oxidizer it strongly supports combustion on any type of fuel. It is such a strong supporter of combustion that it makes readily combustible fuels out of things that are normally imflammable. This includes but is not limited to the containment vessels used to store LOX. High grade 316 Stainless steel itself burns readily in such an oxygen rich environment.

As any boy scout can tell you, the basic fire "triangle" necessary to support combustion requires three things. Fuel, Oxidizer, and ignition source. In any LOX system you have two of the three present at all times. The perfect oxidizer (LOX, often at high pressure in our application) and abundant fuel (the storage vessel AND the vehicle structure in our case). All that is between a LOX system and utter catastrophe on a space vehicle is an ignition source.

Anyone who wants to see what a LOX fire looks like can easily look up both recent Falcon infernos, the Antarres accident last year, or any number of other accidents involving space vehicles that NASA has lost in the past. Much of the evidence of what caused the accident is consumed in the inferno that results from the introduction of an ignition source. However, the charred remains plus existing recorded data can tell the story of what happened if considered in enough detail. We have been quite successful in detailing such causes in the past and I expect we will this time as well.

As the letter in the above article points out, we do have some basic problems in both this investigation and the previous investigation of the Falcon vehicle losses. The first and most glaring problem is that both accident investigations were ran by and controlled by the same private entity that created the vehicle. I would also point out that this same entity, necessarily in an ultracompetitive environment, has a vested interest in coming to a rapid conclusion so that it can get back to the business of making money by launching payloads. This inherent conflict of interest should preclude the possibility that Space Ex heads up its own investigation that will determine when they get back into profitable operation.

Unfortunately, this basic common sense idea seems to be overridden in the present situation just as it was in the last investigation into the loss of a Space Ex vehicle. I would also point out that the something similar just happened in the investigation of the Antarres rocket belonging to Orbital Sciences the exploded shortly after liftoff in Wallops, Virginia last year. Having been personally involved in that investigation, I can assure you that this inherent conflict of interest not only hindered the investigation that NASA's oversight group performed; but eventually precluded the possibility of completely understanding the root cause of the loss of that particular vehicle (more on that a little later).