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# Sikorsky S-76B crash (Kobe Bryant)4

## Sikorsky S-76B crash (Kobe Bryant)

### RE: Sikorsky S-76B crash (Kobe Bryant)

Lot of fog when they took off. Otherwise nothing at this point.

### RE: Sikorsky S-76B crash (Kobe Bryant)

With seven people on board and all their personal belongings, was the helicopter overloaded?

### RE: Sikorsky S-76B crash (Kobe Bryant)

A Sikorsky S-76 can be configured to carry up to 13 passengers, plus a crew of two pilots.

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

### RE: Sikorsky S-76B crash (Kobe Bryant)

Tail number N72EX shows as manufactured in 1991, and powered by twin P&W PT-6s, so most likely an S-76B. Depending on cabin configuration S-76s can carry up to 14 (including 2 aircrew) and the S-76B has a significant SHP advantage over the more common variants powered by Turbomeca 1S or 2S turbines.

In short, with 9 on board, we can’t say for sure it wasn’t overloaded but that wouldn’t be my first guess. He flew in this aircraft A LOT and it was most likely a day trip, wouldn’t expect 500 lbs of luggage.

LAPD allegedly grounded all aircraft this morning due to IFR conditions, and the National Weather Service shows 100% humidity in Topanga from 2:00 AM to about 12:00 this morning.

CFIT in heavy fog seems like a distinct possibility. Just like SRV.

### RE: Sikorsky S-76B crash (Kobe Bryant)

Interesting that except for the turbine/rotor mechanism above the fuselage, the main body configuration is similar to that of a Huey...

Mike McCann, PE, SE (WA, HI)

### RE: Sikorsky S-76B crash (Kobe Bryant)

News reports imply there were mechanical difficulties on the way to Calabasas.

Image of crash site isn't that hilly, so not necessarily CFIT, per se.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm

### RE: Sikorsky S-76B crash (Kobe Bryant)

The Weather Network posted the flight path and the altitude profile.
It looks as though in the last minute of flight the craft abruptly climbed almost 1000 Ft at a high rate of climb and then came down even faster.
Mechanical failure triggered by a high power climb?
Scroll down
The Weather Network attributes Reuters, but I can't find it on the Reuters website.

Oops, I found the original:

Bill
--------------------
"Why not the best?"
Jimmy Carter

### RE: Sikorsky S-76B crash (Kobe Bryant)

Report in the LA Times today states the pilot was flying under special VFR and had requested flight following. Tower responded by saying they were too low for flight following.

Hadn’t seen the altitude data, that’s interesting. LA times says the pilot had sharply increased altitude ‘to avoid a cloud layer’. Maybe mechanical failure due to the climb, or after they were already descending at a high rate?

They describe the crash site as ‘in steep terrain’ but I don’t know that area at all, I’d have to defer to posters who do. LA times report claims the debris grilled is huge- main rotor came to rest 100 yards or more away from the largest parts of the fuselage. Makes me think they still had significant airspeed at impact.

I think some of the aerial photos might be deceiving... just found this, looks pretty steep.

Wondering what the NTSB will be able to turn up since there is not flight data recorder.

### RE: Sikorsky S-76B crash (Kobe Bryant)

This sort of flying is called scud running.

And airline fixed wing flying pressure rating is single digits percentage wise compared to what these corporate charter rotary pilots do.

The customer is usually late, they have a fixed time to get somewhere. 9 times out of 10 if they are using a helicopter then they are picking up and landing off airport with no landings aids/lights. If there are no landing aids they have to be able to get visual with the ground somehow. If there is complete cover of cloud then they have to stay below it for the whole trip. Or go to an airport with landings aids get below the cloud then break off and fly visually to the landing site. But this can add an extra 30 mins onto the flight time.

This guy will have been under the cloud so he can land at his site with his prime. Looking at the flight track he was navigating by following the freeway. The area where he wanted to land was inside an airport control zone. That airport did have landing aids to its runway and had traffic on them. Now Special VFR rules have different rules for ATC than normal VFR. VFR they can presume that the pilot can see and avoid IFR traffic doing approaches into the airport. SVFR they have to positively separate it somehow usually by radar. If the helicopter is so low that it doesn't paint on radar they have a problem and have to increase the separation from 5 miles and 1000ft up to 10 miles and 3000ft. While they are sorting out this unplanned wild zone penetration they still have to keep the traffic flowing onto the main runway. To create a gap it takes 10 mins or so because they have to start playing with the sequence 20 miles out to create a hole. So when the helicopter rocks up, which ATC can't see on radar and know nothing about, they get told to remain clear of the control zone. The pilot then has a problem, they are low, below minimum safe sector altitude and they have restrictions about flying over built up areas. As soon as they start turning they loose their navigation fix which was the freeway. Now we are into how well do they know the local area in good weather. Plus they have the added pressure of there prime has to get to where they are going and they are late already so they will be heading fast towards the control zone boundary and at the last moment been told to remain clear. To note its been 15 odd years since I have flown in the USA so the SVFR rules might have changed.

The rotary peeps can do a thing called quick stop which is where they stick the nose up and give max torque to the main rotor and that kills the forward motion but they keep the same alt. There is also another manoeuvre where they transition the machine to nearly vertical and use gravity to slow it down. When they get to zero speed up wards they swing the back end round using the yaw pedals and then accelerate away in the opposite direction. its called a U turn.

https://youtu.be/iL8LrmySaHI

Here is an example.

I am fixed wing and only flown a helicopter a couple of times. Everything is about the rotor speed and how much torque you are pulling in these sorts of manoeuvres and controlling the yaw. If you let the nr decay your in the poo. Big rotor and two engines you would have to be pulling some amount of torque well over red line to kill the Nr I would have thought in a S76 but if you have a big lump of ground coming towards you needs must.

Said in the nicest possible way about my mates that fly helicopters, they are all slightly off their heads. The machines are in my view death traps before you even start the engines. As soon as you do you are having to constantly fly them because they are fundamentally unstable. They have one nut which keeps the rotor on which is called the Jesus nut. The amount of fuel on board they take off with I would be declaring a mayday before engine start due hitting my min reserve. I have enough for 30 mins holding and 1 instrument approach plus fuel to get to another airport at the absolute minimum at the end of the planned flight. They are happy if there is 30 mins on board plus 5-10 mins left in the tanks. Operating all day inside the dead mans curve is normal. Their close calls happen weekly not every 10 years like mine do and require more luck to survive than mine do to boot as well on fixed wing. The 3 seconds to react which we have been discussing on the MAX threads as being insufficient is an eternity when things go wrong at sub 30 knts and low level which they spend a lot of there time, doing long lining etc.

This video caused quiet a stir in the UK even amongst military pilots. It is the UK special forces helicopter in Wales following a road to try and get out of fog.

https://youtu.be/rNmng0pghG4

Please note I have not expressed an opinion about what has happened in this case just given some pointers about what the general situation setup would have been like and the reasons why the holes in the cheese started lining up. My gut feel though is it will not be an engineering failure.

NTSB will have the preflight paper work. The flight radar24 type plots which have limitations because it was below radar cover. The wreckage which to be honest they can perform miracles with to see if there was a mechanical fault. How the various bits of metal are bent apparently tells a story like reading a book. And various weather statements from witnesses in the area.

Unfortunately the NTSB have vast experience with this sort of accident. Usually though its an air ambulance (HEMS) which has crashed in similar circumstances.

### RE: Sikorsky S-76B crash (Kobe Bryant)

The helicopter was essentially in a dive in the last 20 seconds, going from +1000 fpm to almost -5000 fpm before signal was lost. Unclear how much noise is in the data; a casual estimate would be 300 fpm rms, which makes the one large upblip going from -4000 fpm to -2000 fpm for about 1 second, 8 seconds prior to loss of signal, very curious.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
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### RE: Sikorsky S-76B crash (Kobe Bryant)

The ADS-B plots are becoming more common these days.

You can have your own setup at home for 30$attached to laptop. The problem is the interpretation of the data in accident cases. The aircraft only squirts every so often and the software on the ground works out the secondary values. Is there many birds in the area? Fog tends to kill sound and if a group of birds get a fright and launch and they are scud running it makes for a bad day at work. ### RE: Sikorsky S-76B crash (Kobe Bryant) Am I reading the plot correctly? Subject to the limitations noted, it looks like 153 kts ground speed and -4224 fpm or 48 mph vertically towards the ground and 1700 FT AMSL at the last ADS-B transmission. Bill -------------------- "Why not the best?" Jimmy Carter ### RE: Sikorsky S-76B crash (Kobe Bryant) Medical emergency? That may explain the abrupt blip from -4000 fpm to about -2000 fpm, IRstuff. Bill -------------------- "Why not the best?" Jimmy Carter ### RE: Sikorsky S-76B crash (Kobe Bryant) The FR24 plot makes it look like the pilot was doing a turn left off the Freeway at about 25 miles out from the airport. It is pretty hilly down there and they had circled for 15 minutes in the flight, plus taken what seems like a big detour to the normal route so may be he just ran out of fuel or was looking for a closer airport to put down. Van Nuys airport is about half the distance than his destination. Do they not have GPS on board these things? Maybe that was the ipad the pilot was using?? Remember - More details = better answers Also: If you get a response it's polite to respond to it. ### RE: Sikorsky S-76B crash (Kobe Bryant) The S76 is a twin turbine, single pilot IFR rated helicopter. Which means it also has an autopilot. The fact it was squirting ADS-B means it had at least one integrated GPS on board but more likely it had 3. Flying a heli low level requires both hands and feet working together constantly. If they had had a fuel light on they would have dumped it on the freeway. Edit to add this link with pictures of its cockpit of the aircraft that crashed. It definitely has all the gizmos including autopilot and weather radar. https://www.helis.com/database/cn/51524/ ### RE: Sikorsky S-76B crash (Kobe Bryant) Well the ear witness standing directly under it 20 seconds before impact said the chopper passed about 100 feet over his head going very slowly in-the-clouds turned directly at the nearby hill and flew straight into it with all the sound shutting off at impact. Ear Witness Keith Cress kcress - http://www.flaminsystems.com ### RE: Sikorsky S-76B crash (Kobe Bryant) Talk about strange coincidences... From a 2017 episode of the adult animated sitcom 'Legends of Chamberlain Heights': https://www.youtube.com/watch?v=eLl2qDVi-Vg&fe... John R. Baker, P.E. (ret) EX-Product 'Evangelist' Irvine, CA Siemens PLM: UG/NX Museum: The secret of life is not finding someone to live with It's finding someone you can't live without ### RE: Sikorsky S-76B crash (Kobe Bryant) The transcripts and recordings here https://www.youtube.com/watch?v=RVA3k02lMe8 are quite illuminating. Pilot made to hold while aircraft cleared the other airports and then routed further north to avoid aircraft taking off. Doesn't sound like he ever made contact with the next controller. So maybe decided to abort and return to an airport he could see. Remember - More details = better answers Also: If you get a response it's polite to respond to it. ### RE: Sikorsky S-76B crash (Kobe Bryant) any chance they simply ran into the side of the hill which was obscured by fog? or, maybe a medical emergency and no altitude to accommodate it? Can you tell me what 'fpm' means? It's obviously not feet per minute. Dik ### RE: Sikorsky S-76B crash (Kobe Bryant) dik, pretty sure fpm is feet per minute. This article (which goes into a ton of detail on the weather conditions, Visual Flight Rules, Instrument Flight Rules, and special VFR) states that they climbed 875’ in 36 seconds which would be in line with the rates mentioned here fpm: https://www.washingtonpost.com/weather/2020/01/27/... Seems like a pretty comprehensive read. ### RE: Sikorsky S-76B crash (Kobe Bryant) yes, feet per minute It would seem to be some sort of mechanical thing; seems pretty silly to barreling downward at even 500 fpm in dense fog; even if you don't do a CFIT, you could hit a tree or power line, either would be a bad thing. TTFN (ta ta for now) I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm ### RE: Sikorsky S-76B crash (Kobe Bryant) that article from the Washington post is the best aviation news article I have read in years. It is feet per min. I also agree with it conclusions. Here is quite a good visualisation of the route taken. https://youtu.be/XSHpbGhy3Ko ### RE: Sikorsky S-76B crash (Kobe Bryant) IRStuff: "The helicopter was essentially in a dive in the last 20 seconds, going from +1000 fpm to almost -5000 fpm before signal was lost. Unclear how much noise is in the data; a casual estimate would be 300 fpm rms, which makes the one large upblip going from -4000 fpm to -2000 fpm for about 1 second, 8 seconds prior to loss of signal, very curious." You can have -ve fpm, too. I'm speaking out of ignorance, here. Just want to know. Dik ### RE: Sikorsky S-76B crash (Kobe Bryant) The Washington Post article by Spartan 5 was great... I can see how fog can confuse and be disorienting... I recall travelling across a lake in the fog one night, with a lot fewer degrees of freedom. Spooky. Dik ### RE: Sikorsky S-76B crash (Kobe Bryant) @dik Not sure what you mean. The change from -4000 to -2000 fpm, if real, and not just noise, means the pilot attempted to kill the descent for about 1 second and then resumed the rapid descent. -4000 fpm is 45 mph downward, which is insanely fast for low visibility conditions, even if the pilot thought there was clear air below him, particularly since his altitude wasn't that high, and there's risk of hitting stuff like other aircraft and trees on the way down through the muck. TTFN (ta ta for now) I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm ### RE: Sikorsky S-76B crash (Kobe Bryant) IRS: Thanks... just thought it was too fast... makes sense, now. Dik ### RE: Sikorsky S-76B crash (Kobe Bryant) I down loaded the raw altitude ADS-B data. I suspect that some of those bumps are caused by data lag. There may be a slight lag in the GPS signal. Some one second time windows have more than one data point recorded. The big picture, that is from beginning to end of the final 10 or 12 seconds is more important than relatively small variations in the FPM. Doing an FPM calculation based on the reported data for three consecutive seconds gives a dropping FPM of 4500FPM, 0,and 5250 fpm. When you consider going from a drop of 45 MPH to zero in one second and then an acceleration from zero to almost 60 MPH in one second it is obvious that the data needs to be smoothed, or averages taken over a greater time frame than one second. Bill -------------------- "Why not the best?" Jimmy Carter ### RE: Sikorsky S-76B crash (Kobe Bryant) Or you’ve lost track of which way is up and your body is convinced it is going to die unless you take immediate measures to save it. ### RE: Sikorsky S-76B crash (Kobe Bryant) When rotary looses it, things happen extremely fast, the centripetal forces are colossal as the thing try's to screw itself into the ground. ### RE: Sikorsky S-76B crash (Kobe Bryant) For those of you unfamiliar with the area, the crash site is very near (~2 miles north) of the site where the 1980s TV show MASH was filmed. Many of you will remember the iconic opening scene with the helicopters coming into the medical camp with mountains in the background. The hills where the crash occurred are not as high as those you saw there, but are still substantial. The crash site is just inland of Malibu Canyon, which often provides a path for coastal fog and low clouds to make their way inland. From the flight path reconstruction linked by Alistair above, it appears that the helicopter got squeezed between rising terrain heading west out of the San Fernando Valley and a lower cloud ceiling, and was attempting to turn around and head back to the San Fernando Valley. (A layman's interpretation for what it's worth. ### RE: Sikorsky S-76B crash (Kobe Bryant) I really question the validity of those vertical velocities. If you watch the EAR WITNESS that itsmoked linked to above, he didn't indicate any rapid movements or change in engine sound. He just thought the pilot flew into the hill. ---------------------------------------- The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows. ### RE: Sikorsky S-76B crash (Kobe Bryant) Looks like the pilot might have been changing attitude controls, since the speed curve mirrors the vertical speed, which would not drastically change engine sound, as he might have kept the throttle at the same position. TTFN (ta ta for now) I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm ### RE: Sikorsky S-76B crash (Kobe Bryant) cswilson… I know this area pretty well. The crash site is several hundred yards east of the Las Virgenes Municipal Water District offices and corporation yard. From 1981 to 1986, I worked in Boyle Engineering's Ventura office. During that time, about 80% of my billable hours were on LVMWD projects. Among other things, I worked on the design of a reclaimed water pumping station in the corporation yard and I inspected construction of a 24-inch reclaimed water pipeline that originated at the pumping station. At Wikipedia's coordinates (34.1368°N 118.6923°W), the hillside has an elevation of about 1020 feet. ============ "Is it the only lesson of history that mankind is unteachable?" --Winston S. Churchill ### RE: Sikorsky S-76B crash (Kobe Bryant) An interesting question this all brings up. In a fixed wing aircraft if you suddenly plunged into dense fog you would likely see smooth but still harmful control inputs that would probably result in some reasonably smooth but still fatal CFIT. With a rotary wing craft what would happen? I'm guessing (possibly incorrectly) that the lack of fixed wing 'flies itself' (when trimmed) stability would instead cause very rapid loss of control. Yes/no? Rather like trying to ride a unicycle blindfolded? Keith Cress kcress - http://www.flaminsystems.com ### RE: Sikorsky S-76B crash (Kobe Bryant) My fluids prof way back when called the urge to get there influencing decision making 'Getthereitis' when we were talking about a crash in class (a 14 year old making a trans-us record attempt with her instructor stalled a mooney on takeoff), and my dad said that was the reason he never wanted to learn to fly to travel for business. ### RE: Sikorsky S-76B crash (Kobe Bryant) moon161.... My dad was a helicopter pilot in the California Army National Guard for about 30 years, starting in the mid-1960s. His Air Force training was the big guys: bombers and transports. After leaving the Air Force and spending a couple years not flying, he joined the National Guard as a part-time pilot flying small fixed wing planes used for recon work. When he moved to helicopters he was Captain, but soon went the warrant officer route to avoid a promotion to full-time major that came with a forced transfer to the Los Angeles area. My dad loved flying. He hated chauffeuring generals to parties. One story he told me years ago was about an impatient general who demanded my dad "get this bird in the air" while my dad was going through his pre-flight checklist. My dad ignored the general at first, but finally asked him "Do you want to live or die?" That shut up the impatient general. My dad does not suffer fools. I still need to get my dad's perspective on this crash. I've been too busy to ask him. Fred ============ "Is it the only lesson of history that mankind is unteachable?" --Winston S. Churchill ### RE: Sikorsky S-76B crash (Kobe Bryant) Many years ago in an unnamed Banana Republic, a Supreme Court judge was barnstorming the country campaigning for his favorite presidential candidate. Completely improper but that was life in one of the more corrupt counties in a group of countries noted for corruption. He was traveling in a military chopper. Again, completely improper but that was life in one of the more corrupt counties in a group of countries noted for corruption. He attended a rally on one of the Bay Islands. He wanted to attend another rally and ordered the pilot to take off in a blinding tropical rain storm. They died. Poetic Bill -------------------- "Why not the best?" Jimmy Carter ### RE: Sikorsky S-76B crash (Kobe Bryant) another one for the Darwin awards... Dik ### RE: Sikorsky S-76B crash (Kobe Bryant) I've always thought that a key difference for the rotary wing is that if they got into difficulties like this at least they could really slow down to 40 to 50 mph to figure out where they were, a bit like what he did when in the holding pattern outside the earlier airport. The ground speed was 120mph plus all the way which just doesn't seem like a good plan when you can't see where you're going in hilly terrain. No time to react to terrain warnings or ground proximity. Remember - More details = better answers Also: If you get a response it's polite to respond to it. ### RE: Sikorsky S-76B crash (Kobe Bryant) I think about if the guy had just kept going at 5knots and flown straight into the hill. They'd have probably all survived. Keith Cress kcress - http://www.flaminsystems.com ### RE: Sikorsky S-76B crash (Kobe Bryant) Helicopters frighten me. Ironically, the only time I have been in one was to fly to a pontoon on the Great Barrier Reef to investigate a nearby pontoon where a helicopter went over the side. That was a wheeled Agusta helicopter, and the pontoon had a wooden deck only intended for skid copters. ### RE: Sikorsky S-76B crash (Kobe Bryant) from the BBC... "Island Express Helicopters was restricted to flying under what are known as visual flight rules, meaning pilots must be able to see clearly outside the aircraft in daylight, Keith Holloway, a National Transportation Safety Board (NTSB) spokesman, told the Reuters news agency." Dik ### RE: Sikorsky S-76B crash (Kobe Bryant) Hokie: "Helicopters frighten me." I did a bunch of work in northern Canada and the chopper pilot used to climb when we approached a lake and drop down after we passed it. I asked him if there were some 'lake effects' that could interfere with the flight, and he explained that he didn't swim and by gaining altitute, he could auto-rotate to the shore... I don't know if this is true, but it was the explanation he gave. One of the worst flights I ever had was in a little Cesna... rougher than anything I've experienced since. Dik ### RE: Sikorsky S-76B crash (Kobe Bryant) Back in the 80's, before they changed the rules at Orange County Airport (AKA John Wayne Airport) if you wanted a direct flight to someplace like Chicago or Dallas, you had to fly out of LAX. Rather than driving, you could take a commuter flight in a small plane. Eventually a company started to offer a commuter service using helicopters. I used that service a half dozens times or so as it was very convenient and offered a much better gate-to-gate travel time, until the feds shut them down. Back in those days, American air-service companies had to be more than half-owned by American investors. Anyway, the company was using helicopters manufactured in the UK, and after about a year of service it was discovered that the air-service company owed so much money to the manufacturer, who had provided the aircraft on a finance and fly arrangement, that the feds ruled that in reality it could no longer be considered an American-owned company, so they had to shut down and they never got their fiances straightened-out so they never got back in business. That was the only company offering regular scheduled commuter service in and out of LAX using helicopters. Other than that, I had only been up once before when I was in college. I was home for the summer once when there was a guy who was offering 10-15 minutes flights for something like$25/person (he could take three people at a time). I paid to go up and I took a bunch of pictures including one that showed about 80% of my hometown of Lewiston, MI (and I didn't even have to use a wide-angle lens):

July 1968 (Minolta SR-1)

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

### RE: Sikorsky S-76B crash (Kobe Bryant)

JohnRBaker:

Having grown up in an extremely small village in Maryland, your comment, "...and I didn't even have to use a wide angle lens..." really made me grin! Thanks for making my day.

### RE: Sikorsky S-76B crash (Kobe Bryant)

Two flights in the front seat of an AH-1 Cobra around the foothills near Cucamonga, and UH-60 at Lakehurst NAES. They still had hangars dating to the Hindenberg which were UUGE; I thought the reddish looking trusses and beams were rusty steel, but they were apparently wood.

Oddly, the UH-60 made me seasick; there was a low frequency waddle or nutation. Front seat of Cobra was pretty cool; kind of like sitting on the end of diveboard with nothing below you. Scared of heights, but didn't get sick from that.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm

### RE: Sikorsky S-76B crash (Kobe Bryant)

We still have two blimp hangers here in SoCal. After the Tustin Marine Helicopter base was shut down the property was transferred to the city, they tried to have the hangers torn down, however, they're listed on the National Registry as the largest WOOD structures in the world and thus are protected. Note that they DON'T got back to Hindenburg era as these were built at the beginning of WWII to house Navy blimps which were being used for anti-submarine patrol/warfare off the coast of California. They basically sit empty but have been used as movie sound stage and ti film commercials.

https://www.atlasobscura.com/places/tustin-blimp-h...

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

### RE: Sikorsky S-76B crash (Kobe Bryant)

Aside from the fact that the flight was actually at Lakehurst, their hangars, notably No.1, was the intended destination of the Hindenburg, and Hangars 1 through 4 predate the Tustin hangars, although No.4 was apparently transplanted from Norfolk. Note that Hangar No.1 at Moffett Field predates No.2 at Lakehurst.

Based on the pictures, it looks like we were operating out of Hangar 6, but we could see Hangar 1, particularly when we flew on the test run in the UH-60.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm

### RE: Sikorsky S-76B crash (Kobe Bryant)

Hangar No. 1 at Lakehurst is absolutely massive. I've seen it just about every day of my life (from a distance of about 1 mile over the treeline) and I am still awed every time I go onto the base and see it up close from the ground.

Andrew H.
www.mototribology.com

### RE: Sikorsky S-76B crash (Kobe Bryant)

Same feeling seeing the hangers at Tillamook, Oregon. While there, they had a competitor blimp to the Goodyear ones; it occupied a tiny corner way in the back, like a party balloon in a normal barn. "The hangar building housing the aircraft is 1,072 feet long and 296 feet wide, giving it over 7 acres of area. It stands at 192 feet tall." https://en.wikipedia.org/wiki/Tillamook_Air_Museum The city heavily touts their cheese and a good thing too as the other hanger there burned to the ground being used to store hay and wood. It's too bad; I saw it when it had the WWII aircraft tucked along one side; they have since moved. I suppose it's only a matter of time before the remaining hanger burns as well through accident or lightning or other reason.

" "Hangar B", which is the largest clear-span wooden structure in the world."

The Tustin hangers look to be on the same scale, so I don't know how fine a scale is needed to determine which is the largest.
According to its wikipedia page ..."Tustin, California measures 1,072 feet (327 m) long by 292 feet (89 m) wide by 192 feet (59 m) tall." so just 4 feet narrower? So close.

### RE: Sikorsky S-76B crash (Kobe Bryant)

I've been in there a few times. Crazy big with the scale messing with your head. When you walk towards it it's about 3X farther away than you think.

Apparently Google has leased just about everything there including the hangers. They stripped all the skin off and are refurbishing the hangers sans hazardous materials.

They apparently like running their corporate jets in and out of there better than the San Jose airport. Probably having the same problem that Larry Ellison was having flying his Gulfstream IV into SJO, it closes around 10pm.

Keith Cress
kcress - http://www.flaminsystems.com

### RE: Sikorsky S-76B crash (Kobe Bryant)

The NTSB released a preliminary report on the crash today. Short but does give some new information. Specifically, it looks like the engines were working at the time of the crash and the blades were rotating at the time of impact. Looking more and more like the pilot may have become disoriented in the fog bank.

https://www.ntsb.gov/news/press-releases/Pages/nr2...

### RE: Sikorsky S-76B crash (Kobe Bryant)

The actual report is located here: https://www.ntsb.gov/investigations/Documents/DCA20MA059-Investigative-Update.pdf

The photos included seem to show some amount of visibility, so it's unclear how the pilot got disoriented. Moreover, the pilot was rated for IFR as well being a FAA-certified flight instructor.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm

### RE: Sikorsky S-76B crash (Kobe Bryant)

Its been an extremely long time since a pilot invented a new way of killing themselves.

Just because your qualified doesn't mean your current. And add onto that its a completely different situation when you have planned a IFR flight compared to going IMC as a emergency escape manoeuvre.

Many pilots screw it up in fixed wing which are inherently design to be stable (unless its a 737 MAX of course )

Helicopter its magnitudes harder to do.

The guy might only fly once or twice a year on instruments and his last check could have been months ago under the hood in clear sky's. The company was not licensed to fly IFR and I suspect the machine wasn't maintained to IFR standards. But that's an aside the transition from scud running visual flight to instrument flight is a shock to the system when it happens and has huge scope for things to go wrong very rapidly.

Been there done it in a light aircraft with 800 hours under my belt. 16 years later I haven't repeated the experience.....

### RE: Sikorsky S-76B crash (Kobe Bryant)

The pilot was IFR rated and recently retrained, but interviews with other pilots he flew with indicate he did not have experience flying in fog or cloudy conditions. You may be qualified AND current and still simply lack direct experience with those conditions. It doesn’t take very long for things to go south once you become disoriented.

### RE: Sikorsky S-76B crash (Kobe Bryant)

Apparently the big problem is changing the orientation of the head during accelerated flight producing an incorrect evaluation of the actual acceleration; it seems more than coincidental that the flight deviated at about the same time he would go from looking forward to turning and looking down to change the frequency. While he had done this fine several times before, this may have been the first time he did it on that flight in white-out conditions, so he'd have no horizon or road as reference.

If he had initiated the turn to avoid clouds and then looked down and to the side to change the frequency that might have been enough to initiate the crash sequence. It's one thing to enter white-out straight and level and maintain that; doing so while turning and then complicating the situation may have been too much.

### RE: Sikorsky S-76B crash (Kobe Bryant)

Yep it always bites even when your used to it.

That's why commercial air transport we have two pilots one flies/manages the flight path and machine and the other deals with radios and the rest.

One of the first lessons we teach pilots is

Aviate, navigate then communicate.

### RE: Sikorsky S-76B crash (Kobe Bryant)

Why fly treetops when clear air was just a few hundred feet up?

### RE: Sikorsky S-76B crash (Kobe Bryant)

To avoid losing VFR during a descent back through the clouds and ending up exactly where he ended up.

### RE: Sikorsky S-76B crash (Kobe Bryant)

Have helicopters got a spiral dive mode that feels ok by the seat of the pants (resultant vector normal to the cockpit floor) but is headed into the ground?

### RE: Sikorsky S-76B crash (Kobe Bryant)

That NTSB report is as usual full of information.

It states the last transmission was that the pilot was climbing up to 4000 ft to make himself visible to radar and be above the cloud layer.

The plot of the last part of the flight seems to bear this out with the helicopter climbing steadily before then for reasons unknown starting a banking dive to the left.

Would it really be that hard to maintain level climbing flight in a straight line??

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

### RE: Sikorsky S-76B crash (Kobe Bryant)

The spiral dive is a mode covered in the flight dynamics course I took [edit, Thank You Bill Rae, UB emeritus], a coordinated descending turn. Absent a pilot, a paper airplane trimmed for straight and level flight can enter it if perturbed, IIRC. [edit- I don't have enough of a clue about helicopter stability and control to say if this flight mode directly applies to a helicopter.]

Edit: Spiral dive flight mode:
http://www.skywalker.ca/Flying_Stories/Bob_s_Stori...

This also relates to the graveyard spiral, where for a passenger or pilot, absent horizon cues, nothing is going to seem wrong because the net vector is normal to the floor when flying this coordinated descending turn. This excerpt talks about how straight and level can seem to be the deviation if the inner ear is spinning long enough.

#### Quote (Graveyard spiral wiki)

The graveyard spiral is associated with a return to level flight following an intentional or unintentional prolonged bank turn. For example, a pilot who enters a banking turn to the left will initially have a sensation of a turn in the same direction. If the left turn continues (~20 seconds or more), the pilot will experience the sensation that the airplane is no longer turning to the left. At this point, if the pilot attempts to level the wings this action will produce a sensation that the airplane is turning and banking in the opposite direction (to the right), a sensation commonly known as "the leans". If the pilot believes the illusion of a right turn (which can be very compelling), he/she will re-enter the original left turn in an attempt to counteract the sensation of a right turn. If the pilot fails to recognize the illusion and does not level the wings, the airplane will continue turning left and losing altitude.[5] Because an aircraft tends to lose altitude in turns unless the pilot compensates for the loss in lift, the pilot may notice a loss of altitude. The absence of any sensation of turning creates the illusion of being in a level descent. The pilot may pull back on the controls in an attempt to climb or stop the descent. This action tightens the spiral and increases the loss of altitude.[6]

The solution, of course, is for the pilot to consciously override the brain's imperative to judge physical altitude on the basis of signals from the vestibular, and rely solely on the visual cues of horizon or of altitude instruments in the airplane, until the brain once again adjusts, and vestibular sensory input agrees with visual input.

https://en.wikipedia.org/wiki/Graveyard_spiral

### RE: Sikorsky S-76B crash (Kobe Bryant)

Still seems very odd, particularly these days. 25 years ago, a helicopter might have had to scab a GPS by sticky taping one to the dash, but that helicopter should have had at least the equivalent of a basic Garmin car nav system, which would have shown that they were veering 180 degrees away from their destination. They were following the 101 freeway, and the helicopter was ostensibly visible from the ground, so also vice-versa, and then the pilot turned away from their course in the last 20 seconds.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm

### RE: Sikorsky S-76B crash (Kobe Bryant)

CFIT gives me the willies. I only have about 100 hours in Cessnas, and I'm glad most of it is on the coast. I've only headed up to the mountains a few times, and was paranoid in the extreme.

Flying in and around heavy clouds/fog is no fun, either. I couldn't imagine combining the two. My first solo was on a day with weather moving in (as it does nearly every day in the summer). My instructor and the chief pilot both agreed that there was enough room for me to get a couple turns around the pattern before I'd need to come in and still have a reasonable factor of safety. I was at 700ft MSL (which is only about 690ft AGL here) climbing out - first time alone in an airplane - when I hit a cloud. I had to break pattern at a "small" international airport and get back on the ground with conditions degrading a lot faster than anyone thought. My PIREP ended VFR that day. One of the scariest things that's ever happened to me.

As for the pilot's last minute turn...maybe he dropped is iPad and tried to reach for it...

### RE: Sikorsky S-76B crash (Kobe Bryant)

You lot are trying to compare flying a fixed wing to flying a helicopter its a completely different ball game.

Pitch plus power = performance doesn't work the same way. And they have loads of gyroscopic tendency's to deal with.

Plus its extremely easy to get into attitudes where the gyros topple.

I don't know if a left turn like that is a common mistake, it may be linked to the direction of yaw when you apply torque to the main rotor. I think helicopters use bits of string on the windows to see yaw.

### RE: Sikorsky S-76B crash (Kobe Bryant)

I get something like a 0.6 g turn; that seems a bit drastic for flying in limited visibility

He still had gobs of instruments telling him the same story, over the course of at least 40 seconds
> GPS moving map
> Attitude display system
> Instrument display system
> Horizontal situation indicator

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm

### RE: Sikorsky S-76B crash (Kobe Bryant)

#### Quote (Wikipedia)

The solution, of course, is for the pilot to consciously override the brain's imperative to judge physical altitude on the basis of signals from the vestibular, and rely solely on the visual cues of horizon or of altitude instruments in the airplane, until the brain once again adjusts, and vestibular sensory input agrees with visual input.

I fly sailplanes and small airplanes, and for a dozen years I commuted two or four times a week on a six-seat airplane on which about 30% of our flights involved descending through cloud on IFR approaches. In my experience, it is difficult to explain to someone how hard it is to ignore sensations from the inner ear and rely instead on instruments. The sensations are very strong, and disregarding them, or at least compartmentalizing them as invalid, is a skill that takes experience to master, and which atrophies with disuse. In the absence of that skill, one is spring-loaded to trust their inner ear over the instruments.

### RE: Sikorsky S-76B crash (Kobe Bryant)

I am under the impression that normally the pilot will have his left hand on the collective and his right hand on the cyclic control.
When the pilot is changing channels on the radio, what is his hand position?

Bill
--------------------
"Why not the best?"
Jimmy Carter

### RE: Sikorsky S-76B crash (Kobe Bryant)

They can trim the cyclic and also the collective.The left hand is on the collective.

The normal way is to take the hand off the collective for a couple of seconds. Alot of collectives they can change the frequency on a consol on the collective.

You can hear helo pilots getting a bit narked when ATC give them frequency changes while hovering.

He will have been pulling lots of collective to do the IMC escape climb.

This guy day in day out apart from check rides will be flying looking out the window.

here is the cockpit of the helicopter that crashed.

### RE: Sikorsky S-76B crash (Kobe Bryant)

I just read an article where a decades-of-helicopter-flying chief pilot stated that flying a helicopter without visible clues up thru clouds results in disaster approximately 80% of the time if the pilot also makes the fatal error of attempting to turn while in the maneuver.

Keith Cress
kcress - http://www.flaminsystems.com

### RE: Sikorsky S-76B crash (Kobe Bryant)

My theory has always been that helicopters fly by being so ugly the ground refuses to touch them. But with fog the ground can't see the helicopters, so they crash!

### RE: Sikorsky S-76B crash (Kobe Bryant)

Eufalconimorph I completely agree with your analysis.

I won't go in one if I can help it.

### RE: Sikorsky S-76B crash (Kobe Bryant)

IR stuff you need to go and have a play in a R22.

The contraptions fall out of the sky for the slightest excuse.

### RE: Sikorsky S-76B crash (Kobe Bryant)

One of my former employers used to use helicopters for access to specific sites, although I didn't end up getting to those specific sites.
At one stage they became a bit more cognisant of some of the issues specific to that form of transport and put some of their staff through HUET (training). If some of the videos of people undertaking that sort of training aren't disconcerting, I don't know what is. The training my colleagues received was a lower impact version, but I'm not sorry I missed out on those trips as a result.

### RE: Sikorsky S-76B crash (Kobe Bryant)

Helicopter Underwater Escape Training

Bill
--------------------
"Why not the best?"
Jimmy Carter

### RE: Sikorsky S-76B crash (Kobe Bryant)

#### Quote (waross)

Helicopter Underwater Escape Training

Been there, done that. When I went through flight qualification as a civilian employee of the US Navy I strapped into a seat of a pseudo helicopter to be dunked into a pool and then get flipped upside down under water. Seemed to have managed to get out satisfactorily.

### RE: Sikorsky S-76B crash (Kobe Bryant)

The HUET training these days is mild compared to the 80/90's.

RGIT in Aberdeen used to give you a near death experience. They chilled the pool down to North Sea temperatures. A Wave machine going, a big fan blowing water in your face, pitch black and then you got turned upside down and had to escape and get into rafts.

But they had to tone it down because people were resigning rather than having to do it again. So these days its done in a nice warm pool, lights are all on, no waves. And the instructors aren't Royal Navy ex clearance divers. Its actually quiet good fun.

### RE: Sikorsky S-76B crash (Kobe Bryant)

#### Quote (Itsmoked)

I just read an article where a decades-of-helicopter-flying chief pilot stated that flying a helicopter without visible clues up thru clouds results in disaster approximately 80% of the time if the pilot also makes the fatal error of attempting to turn while in the maneuver.
And in the middle of a turn in the clouds he was changing radio frequencies?
Ouch!

Bill
--------------------
"Why not the best?"
Jimmy Carter

### RE: Sikorsky S-76B crash (Kobe Bryant)

#### Quote (davidbeach)

Seemed to have managed to get out satisfactorily.

Explains a lot, doesn't it folks.

Keith Cress
kcress - http://www.flaminsystems.com

### RE: Sikorsky S-76B crash (Kobe Bryant)

He probably wasn't changing frequency's but he might have been switching because he was climbing into controlled airspace. I also don't think he would have been in the turn when he started changing freq if that is what he was doing, he was also probably climbing as well. Changed freq and when he looked up he was descending like a brick and his yaw was out of control. Then he was dead.

Some are shall we say over dramatized about getting in conversations with the feds and or having to talk to ATC watch managers because they have screwed up....

Its a pretty hostile ATC environment around lax. There isn't a lot of free air available and the controllers are well known for being stroppy.

In reality they would deal with it. You wouldn't get issues with prioritising flying the machine and then sorting ATC once your safe. You might have discussions why you were in the situation in the first place though.

I don't know what they are like in that area, I have only flown in Florida airspace. I have heard aircraft get themselves into a hole in FL and Orlando where utterly superb dealing with it. After about 30seconds there was a change of voice to a older lady who announced herself as a controller and a CFII and she was going to teach them how to fly on instruments. She got them safely into VMC..

There is an often quoted statistic that a VFR fixed wing pilot going into IMC has an expected life span of 75 seconds after entering cloud. Helicopters its under 60 seconds.

### RE: Sikorsky S-76B crash (Kobe Bryant)

AH: "He probably wasn't changing frequency's but he might have been switching because he was climbing into controlled airspace. I also don't think he would have been in the turn when he started changing freq if that is what he was doing, he was also probably climbing as well. Changed freq and when he looked up he was descending like a brick and his yaw was out of control. Then he was dead."

Real plausible...

Dik

### RE: Sikorsky S-76B crash (Kobe Bryant)

Somewhere earlier there was a point made that the pilot had to wear corrective lenses (reading glasses?) to see the instruments, if he didn't have bifocals or low-rise cheaters on, there could be a delay in trying to don spex to see the panel/switches, adding to the possibility of confusion/lack of situational awareness. I question his decision in trying to terrain-follow in the first place given the fog/clouds, but get that it's easier to do ad-hoc flights at low altitude than file a flight plan through controlled airspace. I'm sure there was pressure from the VIP client to make the flight as well.

### RE: Sikorsky S-76B crash (Kobe Bryant)

he could have also been wearing polarising sunglasses which stop you seeing the screens properly.

Just going to have to wait for the report.

### RE: Sikorsky S-76B crash (Kobe Bryant)

He wasn't terrain following, per se, he was following the freeway, and so it must have been visible at least until he got through the pass, although he was climbing immediately afterwards

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm

### RE: Sikorsky S-76B crash (Kobe Bryant)

(OP)

#### Quote (Alistair Heaton)

he could have also been wearing polarising sunglasses which stop you seeing the screens properly.

### RE: Sikorsky S-76B crash (Kobe Bryant)

Speaking of out-of-date computer hardware, based on a display I saw years ago at the now defunct 'Boston Computer Museum', the last operational computers which utilized vacuum tube technology, were ones that were part of the nation's air-traffic control system. If I recall correctly, it wasn't until the late 1990's before the last vacuum tube systems were replaced with solid-state equipment. There's a story about how in 1995, Bill Clinton, in one of his bipartisan moments, was heard complaining to then Speaker of the House Newt Gingrich, that it was a travesty that the FAA was forced to procure replacement parts (vacuum tubes) from former Communist-bloc nations as they were the last place where they were still being manufactured.

I can relate to this as one of my hobbies is old radios, and my pride and joy, a 1965 Hammarlund HQ-180A, uses vacuum tubes.

When I acquired the radio back in 1999, I needed to replace several of the tubes which were broken. I finally found a guy in Mesa, AZ, who had a warehouse stocked with over a million vacuum tubes. The vast majorities of his inventory came to him when the Pentagon would close a military base and they would literally sell off stuff like that by pound. Since my Hammarlund was based on a military design, I had no problem getting the tubes that I needed.

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

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