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.
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.
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.
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.
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.
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.
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!
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.
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
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"Why not the best?"
Jimmy Carter
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.
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.
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.
