FDR: comment not relevant to the accident ( I’m sure ) but relevant to the numbers you posted, except for the turn part. In doing flight load survey data gathering, the flight test cards at SA always add in a maneuver called a rough approach. The pilot has to find it for that particular days wind and the weight/speed. Typically 15-30Kts and 800-1500 fpm descent. Mechanism is the advancing rotor entering the tip vortex from the preceding blade. One can sit in it and it will definitely rattle the ship at the N/rev frequency. It can produce vibratory stresses that can enter into the fatigue life calculations for things like engine mounts to top deck items. Aircraft that sit in this regime a lot, like S-64 logging for instance, have seen the resultant need for structure beef-up. Ok, just background-not applicable to subject at hand.

Airplane,

Nice effort and interesting result!

As you manipulated the data into the graphic you produced.....what do you see in the last 10-20 seconds that piques your interest the most?

What do you see as to ROD and Airspeed (can we discern Airspeed vs Ground Speed from the raw data compared to the Weather Data for Wind direction and velocity?)?

Would this aircraft be fitted with CVFDR?

I would bet that it was not.

It will be interesting to se if VRS recovery was on the menu for that flight and, if so, what recovery technique was going to be employed.

In no particular order:

1) I am circumspect of the last few altitude readings (where it climbs fast) because they are inconsistent with ADS-B vertical rates, a 200' climb in two seconds at low ground speed seems improbable, and the delta between the baro and geo heights changes at the end. There are two possible reasons for these inconsistencies that I can think of:

• a) There was unusual pressure on the static ports due to unusual aerodynamic maneuvers, and that caused inaccurate PA readings.
• b) We are missing some ADS-B velocity messages, and those messages contain positive vertical rates and geo deltas that are consistent with the altitude gain.

2) The horizontal jitter in the ground track is consistent with 5m ADS-B precision and accuracy. It doesn't mean the aircraft was actually bouncing around as shown.
3) Why did the helicopter ground speed drop to near 0 at the end? What events led to that?
4) Why did we lose the signal at such a high altitude? Earlier in the flight, only a couple of miles away, ADS-B exchange received the signal as low as 775'.

I haven't spent any time thinking about factors like wind.

Edit: Credit where credit is due. A lot of the work in the visualization is courtesy of adsbexchange.com

Those questions track with my thoughts....and your comment about unusual aircraft movements confusing the Pitot Static system and data reporting based upon that all seem to suggest those might be correlated with a catastrophic failure of some kind.

Which leaves us without the bigger question of what kind of failure it was and why?

The basic Bell 429 has a "FDR" recording function in each of the flight displays which records traditional FDR parameters at a rate of 1/2 seconds (2 Hz). As there was no fire this data should be retrievable.

Is it possible the P&W engine controls incorporated a history recorder of some sort and have some data to provide? Actually, the same goes for the SAS or autopilot if the aircraft has such.There is one aircraft I know of wherein a chip to do that was added to the AFCS, tho’ not required nor paid for by the customer. The engineer who did that was suitably revered for doing it, but never, that I know of, suitably rewarded.

FYI: EMS helicopters are required to have a Flight Data Monitoring System installed per Part 135. Its not the same as a FDR but it records a number of data points that can be downloaded and reviewed graphically with some recording ambient cockpit audio and video. A number of EMS operators also have actual CVR-FDRs installed as well so there should be plenty of data to see what the aircraft was doing prior to the incident. And yes the PW207 does have a field-downloadable DCU that will give engine data in various formats depending on the software used to view the data.

Wrench, any chance that DCU gets a collective position signal?

On the wind, the circuits that had been flown were consistent with a wind from the west, which suggests that the CAS would have been higher after the left-hand U-turn than before. We may be looking at the wrong issue here in considering VRS. The debris and component state will be telling. Does the 429 have a hydraulic actuator saturation issue like one of the friendly European country's product?

I don't have the winds at 2000', but here is the METAR from the local airport that showing winds from the west:

KGVQ 261656Z AUTO 28011KT 10SM BKN033 OVC043 09/02 A3007 RMK AO2

KGVQ 261656Z AUTO 28011KT 10SM BKN033 OVC043 09/02 A3007 RMK AO2 KGVQ 261656Z AUTO 28011KT 10SM BKN033 OVC043 09/02 A3007 RMK A

KGVQ 261656Z AUTO 28011KT 10SM BKN033 OVC043 09/02 A3007 RMK AO2

LRP pointed out to me that had I looked a bit earlier, I would see that the helicopter performed a descent, recovery, and climb out, prior to the time period I depicted. Here is an animation of the last 3 minutes, at 3x speed, showing that:


I will leave it to those more knowledgeable than me to evaluate whether this sequence is consistent with VRS recovery training.

I don't know if the DCU stores the CLP signal. Then again I don't recall ever looking for it in past downloads. The CLP is sent to the EEC first for processing then if it fits the criteria it is saved to the DCU. In some cases, engine data, events, exceedances, etc. are saved in both the EEC and DCU. If the EEC and DCU can be downloaded then there should be a very detailed engine performance report to include the CLP. Regardless, the latest info out is the wreckage spans over 1000 linear feet with the persistent rumor of an inflight break-up.

While not related to this incident an AD was released on the same day pertaining to 429 T/R P/C links.....
https://rgl.faa.gov/Regulatory_and_G...2022-09-07.pdf

02/27/2018 appears to be when the Tail Number was assigned to the aircraft.

NTSB Preliminary Report issued. https://data.ntsb.gov/carol-repgen/a...ort/105004/pdf

Main rotor blade Vs tail boom. Could be cause or effect of something else. I recall an EC135 crash in Arizona in 2010 that severed it's own tail boom - in that case it was a rapid drop in collective (child stepped on it) followed by extreme recovery by pilot (full up collective and full aft cyclic). Perhaps in this case an overzealous auto entry by the student was corrected by the instructor - seems a bit extreme? The EC135 has a rigid rotor head and managed the feat so seems possible on the Bell 429 but would a Bell IP react like that?

Or a large application of collective combined with aggressive lateral cyclic and yaw inputs.......................