tag:blogger.com,1999:blog-3991004594884305625.post1330626505366311464..comments2020-02-15T03:12:34.705-08:00Comments on Satcom Guru: Flawed Assumptions Pave a Path to DisasterPeter Lemmehttp://www.blogger.com/profile/16409315777756590084noreply@blogger.comBlogger4125tag:blogger.com,1999:blog-3991004594884305625.post-85396813052700497702019-11-01T00:53:25.348-07:002019-11-01T00:53:25.348-07:00On the other hand, if the airplane is outside of t...On the other hand, if the airplane is outside of the normal flight envelope and the malfunction of MCAS is still HAZARDOUS, then there is no discount in malfunction rate.<br /><br />The malfunction rate, once you are outside the normal flight envelope, should still be 1E-7 malfunctions per hour.<br /><br />As a matter of fact, the dependency of A) OFE and B) MCAS runaway is extremely strong. If B) occurs in NFE, the probability for A) becomes 1 = 100%. Thus, the probability for B)alone is equal to the probability for A)&B) combined. The "discount" is plainly wrong.Spornradhttps://www.blogger.com/profile/13499648828513945851noreply@blogger.comtag:blogger.com,1999:blog-3991004594884305625.post-67346274285092633452019-10-30T05:55:19.643-07:002019-10-30T05:55:19.643-07:00after my third re-read:
Math error concerning the...after my third re-read: <br />Math error concerning the combination of probabilities committed by Boeing. Combined event probability is multiplied single event prob only if events are independently random! In this case, MCAS has the power to bring the plane out of normal speed envelope, and MCAS is designed to trigger outside of normal envelope. Therefore the single events are by no means independent.<br />https://www.statisticshowto.datasciencecentral.com/probability-and-statistics/dependent-events-independent/Spornradhttps://www.blogger.com/profile/13499648828513945851noreply@blogger.comtag:blogger.com,1999:blog-3991004594884305625.post-12343236703153172032019-10-29T19:36:32.743-07:002019-10-29T19:36:32.743-07:00Hi Peter, seems vital work. As ex UN career staff ...Hi Peter, seems vital work. As ex UN career staff who lost colleagues in the Addis crash, I know IMO would be all over this if it were maritime, ITU if telecomms, WHO if health, on and on. So why is ICAO barely being mentioned anywhere including not by you? If FAA/NTSB and the Euro equivalent are stiffing them, that seems another red flag for your list. Peter QuennellUnknownhttps://www.blogger.com/profile/11950450198628216286noreply@blogger.comtag:blogger.com,1999:blog-3991004594884305625.post-87307372645190481782019-10-29T03:17:15.702-07:002019-10-29T03:17:15.702-07:00Thanks Peter, great piece- albeit hard for me to g...Thanks Peter, great piece- albeit hard for me to grasp all the aspects.<br />Is this a typo? You write: ... This leads to approving a system with one-tenth the integrity to achieve a MAJOR hazard as acceptable for a HAZARDOUS hazard. It DOES make numerical sense. <br />You mean: it DOES NOT ??Spornradhttps://www.blogger.com/profile/13499648828513945851noreply@blogger.com