Lucas James Knight
Lawrence "Larry" John Schlichting
Grace Addae
The National Transportation Safety Board did not travel to the scene of this accident.
Additional Participating Entities:
Federal Aviation Administration / Flight Standards District Office; Minneapolis, Minnesota
Lycoming Engines; Williamsport, Pennsylvania
Textron; Wichita, Kansas
Investigation Docket - National Transportation Safety Board: https://data.ntsb.gov/Docket
Harrier Aviation LLC
Location: Cottage Grove, Minnesota
Accident Number: CEN20LA392
Date and Time: September 13, 2020, 14:32 Local
Registration: N8488L
Aircraft: Cessna 172
Aircraft Damage: Destroyed
Defining Event: Unknown or undetermined
Injuries: 3 Fatal
Flight Conducted Under: Part 91: General aviation - Personal
On September 13, 2020, at 1432 central daylight time, a Cessna 172, N8488L, was destroyed when it was involved in an accident near Cottage Grove, Minnesota. The flight instructor and two passengers were fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations (CFR) Part 91 personal flight.
According to the operator, the accident flight was a “discovery flight” arranged by the passenger for his girlfriend. Discovery flights typically included 1/2 hour of ground training and a preflight inspection of the airplane, followed by the flight, during which the front-seat passenger operated the controls to the extent possible. The male passenger was seated in the right rear seat, the female passenger was seated in the left front seat, and the flight instructor was seated in the right front seat.
According to Automatic Dependent Surveillance-Broadcast (ADS-B) data, the airplane departed about 1428 and proceeded southbound until it crossed the Mississippi River, then it turned to a southeast heading. The last return from the airplane was at 1432, over Lower Grey Cloud Island at an altitude of about 1,900 ft and speed of 101 mph. The flight profile view revealed a sharp descent followed by a sharp ascent as the airplane approached Lower Grey Cloud Island; the airplane subsequently entered a steep descent that continued until impact. An aircraft performance study based on the ADS-B information indicated that the airplane lost over 1,000 ft of altitude in seven seconds: a descent rate of over 8,000 ft per minute, before impact.
The pilot of another airplane, inbound to the departure airport, had a Go-Pro video camera operating in the cockpit and captured the accident airplane as it descended. Although eagles or geese were seen in the area, there was no evidence to indicate that the accident airplane collided with any of these birds.
Pilot Information
Certificate: Commercial; Flight instructor
Age: 23, Male
Airplane Rating(s): Single-engine land; Multi-engine land
Seat Occupied: Right
Other Aircraft Rating(s): None
Restraint Used:
Instrument Rating(s): Airplane
Second Pilot Present:
Instructor Rating(s): Airplane multi-engine; Airplane single-engine; Instrument airplane
Toxicology Performed: Yes
Medical Certification: Class 1 Without waivers/limitations
Last FAA Medical Exam: October 22, 2019
Occupational Pilot: Yes
Last Flight Review or Equivalent:
Flight Time: 300 hours (Total, all aircraft), 300 hours (Total, this make and model), 47 hours (Last 90 days, all aircraft)
Aircraft and Owner/Operator Information
Aircraft Make: Cessna
Registration: N8488L
Model/Series: 172I
Aircraft Category: Airplane
Year of Manufacture: 1968
Amateur Built:
Airworthiness Certificate: Normal
Serial Number: 17256688
Landing Gear Type: Tricycle
Seats: 4
Date/Type of Last Inspection: July 17, 2020 Annual
Certified Max Gross Wt.: 2299 lbs
Time Since Last Inspection:
Engines: 1 Reciprocating
Airframe Total Time: 3343 Hrs as of last inspection
Engine Manufacturer: Lycoming
ELT: Installed, not activated
Engine Model/Series: O-320-E2D
Registered Owner:
Rated Power: 160 Horsepower
Operator:
Operating Certificate(s) Held: None
Meteorological Information and Flight Plan
Conditions at Accident Site: Visual (VMC)
Condition of Light: Day
Observation Facility, Elevation: SGS,821 ft msl
Distance from Accident Site: 6 Nautical Miles
Observation Time: 14:35 Local
Direction from Accident Site: 335°
Lowest Cloud Condition: Clear
Visibility 10 miles
Lowest Ceiling: None
Visibility (RVR):
Wind Speed/Gusts: 3 knots /
Turbulence Type Forecast/Actual: None / None
Wind Direction: 190°
Turbulence Severity Forecast/Actual: N/A / N/A
Altimeter Setting: 30.1 inches Hg
Temperature/Dew Point: 21°C / 14°C
Precipitation and Obscuration:
Departure Point: South St, Paul, MN (SGS)
Type of Flight Plan Filed: None
Destination: South St, Paul, MN (SGS)
Type of Clearance: None
Departure Time: 14:28 Local
Type of Airspace: Class G
Airport Information
Airport: So. St. Paul Municipal SGS
Runway Surface Type:
Airport Elevation: 821 ft msl
Runway Surface Condition:
Runway Used:
IFR Approach: None
Runway Length/Width:
VFR Approach/Landing: None
Wreckage and Impact Information
Crew Injuries: 1 Fatal
Aircraft Damage: Destroyed
Passenger Injuries: 2 Fatal
Aircraft Fire: None
Ground Injuries:
Aircraft Explosion: None
Total Injuries: 3 Fatal
Latitude, Longitude: 44.810981,-92.919792(est)
The wreckage was located in 70-foot-deep water and was examined at a secure facility following recovery. All control cables failed at or near their cockpit connections and the failures were consistent with overload. The cables were traced from the cabin area to their respective flight control surfaces.
Both wings displayed accordion-type compression damage aft to the main spar, consistent with highspeed impact. The left horizontal stabilizer had more impact damage than the right horizontal stabilizer.
The vertical stabilizer, although straight, was impact damaged, but the anticollision light on top of the tail was intact, consistent with the airplane being upright upon impact. The damaged propeller blades were bent aft into the engine compartment. The examination of the engine revealed no anomalies that would have precluded normal engine operation.
Medical and Pathological Information
The Ramsey County Medical Examiner performed the CFI’s autopsy; cause of death was multiple traumatic injuries, aircraft accident, and his manner of death was accident. The Federal Aviation Administration Forensic Sciences Laboratory identified ethanol at 0.051 g/dL in cavity blood and did not detect ethanol in urine.
===========
Location: Cottage Grove, MN
Accident Number: CEN20LA392
Date & Time: 09/13/2020, 1432 CDT
Registration:N8488L
Aircraft: Cessna 172
Injuries:3 Fatal
Flight Conducted Under: Part 91: General Aviation - Personal
On September 13, 2020, at 1432 central daylight time, a Cessna 172I airplane, N8488L was destroyed when it was involved in an accident near Cottage Grove, Minnesota. The pilot and two passengers were fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations (CFR) Part 91 personal flight.
Radar data showed the airplane depart SGS at 1428, climbing to about 1,800 ft mean sea level, and proceed southbound before it turned southeast-bound over Upper Grey Cloud Island. At 1432, over Lower Grey Cloud Island, the target disappeared. Another airplane, inbound for landing at SGS, captured N8488L in a video and still photographs as it descended. Examination of the photographs indicated the airplane appeared to be intact.
Some wreckage was located and recovered on September 14, 2020. The majority of the wreckage (about 90 percent) was recovered on September 19, 2020. The wreckage has been taken to a secure location where it will be further examined.
Aircraft and Owner/Operator Information
Aircraft Make: Cessna
Registration: N8488L
Model/Series:172 I
Aircraft Category: Airplane
Amateur Built: No
Operator: Harrier Aviation
Operating Certificate(s) Held: None
Meteorological Information and Flight Plan
Conditions at Accident Site:
Condition of Light:
Observation Facility, Elevation: SGS
Observation Time:
Distance from Accident Site:
Temperature/Dew Point:
Lowest Cloud Condition:
Wind Speed/Gusts, Direction:
Lowest Ceiling:
Visibility:
Altimeter Setting:
Type of Flight Plan Filed:
Departure Point:
Destination:
Wreckage and Impact Information
Crew Injuries: 1 Fatal
Aircraft Damage: Substantial
Passenger Injuries: 2 Fatal
Aircraft Fire: None
Ground Injuries: N/A
Aircraft Explosion: None
Total Injuries: 3 Fatal
Latitude, Longitude:
The name of the third and final occupant of the plane that crashed in a water-filled quarry last week on Grey Cloud Island in Cottage Grove has been released.
According to the Ramsey County Medical Examiner’s Office, Grace “Gracy” Addae, 30, Eden Prairie, died in the fatal crash.
Addae was in the airplane with Larry Schlichting, 60, of Eagan, and Lucas Knight, 23, of North Mankato, Minn. All three died in the crash.
The three were reportedly on a “discovery flight” Sept. 13 from Fleming Field Municipal Airport in South St. Paul, a flight designed to provide a prospective aviation student a chance at the controls.
Addae, who was born and raised in Ghana, emigrated to Minnesota about a decade ago, said her friend, Leah Chepkwony, of Eden Prairie. She was a certified nursing assistant and was studying nursing, according to Chepkwony, who said Addae lived with her at her house in Eden Prairie for almost a year, but had moved out in late July.
Chepkwony believes Addae met Schlichting in August when Addae was “sent by an agency to take care of Larry’s mom,” she said. The two later collaborated on YouTube projects, according to social-media posts.
Schlichting was a senior technical writer for MTS Systems in Eden Prairie.
Knight worked as a flight instructor for Air Trek North at Fleming Field. Originally from Coon Valley, Wis., Knight had been a licensed commercial pilot since June 2019. He graduated from Minnesota State University, Mankato, in December 2019 with a degree in aviation and a concentration in professional flight. “His roommates dubbed him a nerd due to the amount of time spent reading about aviation and studying his note cards,” his obituary states.
“Lucas loved being outdoors and being active, whether it was going for a run, bicycling, riding his motorcycle, or being on the water with friends,” his obit states. “He loved trying new foods, was considered an expert by many on being able to pull off a smorgasbord of innocent pranks and was absolutely ga-ga over Teslas.”
Knight, the eldest of three children, attended school in Westby, Wis., graduating from high school in 2015. He was actively involved in cross-country and band and had also wrestled and run track, according to his obituary.
He worked at Shopko while in high school and at the Ace Hardware Distribution Warehouse after graduation. During college, he worked at Best Buy, and he had recently started a part-time job driving for FedEx in the Owatonna area.
Knight loved making new friends, electronic devices and reading, according to his obituary. “He was an avid reader from an early age and the sense of taking him on vacation was at times questioned since he always had a book to his nose,” his obit states.
Lucas Knight, 23, of North Mankato, died in a plane crash on Sept. 13, 2020.
“Lucas had a million-dollar smile and it would be his earnest desire for those saddened by his departure from this earth to improve yourself, inspire others, and keep moving forward,” his obit states. “The family would like to thank law enforcement and the search-and-rescue teams for their dedicated work, and to family, friends and the community for their outpouring of love and support.”
Knight is survived by his parents, Dennis and Lisa Knight, and his siblings, Dani and Ryan.
A memorial visitation will be noon to 4 p.m. Sunday at the Coon Valley, Wis., American Legion Hall. Attendees are asked to wear a mask. The Seland Funeral Home in Coon Valley is handling the arrangements.
According to FlightAware.com, a service that tracks flights, a single-engine Cessna Skyhawk took off from Fleming Field at 2:28 p.m. on Sept. 13. It was last seen four minutes later.
Officials were notified that the plane was missing around 8 p.m. They found the first sign of wreckage — a tire from the airplane — around 11 p.m. in the quarry on Lower Grey Cloud Island. The pit is operated by Aggregate Industries.
Washington County Sheriff Dan Starry said the search was difficult because the plane was found more than 70 feet underwater. Dive teams recovered the bodies of Knight and Schlichting on Tuesday; Addae’s body was recovered Thursday.
Minnesota officials identified the third occupant of the plane that crashed September 13 on an island in the Mississippi River.
Three people were onboard a small plane that crashed in a water-filled quarry on Grey Cloud Island in Washington County. All three people died in the crash.
The Ramsey County Medical Examiner identified the third occupant as 30-year-old Grace Addae of Eden Prairie. The other two occupants were identified as Larry Schlichting, 60, of Eagan and Lucas Knight, 24, of North Mankato.
Authorities said the Cessna 172I Skyhawk left Fleming Field Municipal Airport in South St. Paul on the afternoon of Sept. 13. The plane lost radar contact, and by the evening, the airport had reported it missing.
Crews had focused their search for the plane on a deep, water-filled quarry and located some of the wreckage from the plane more than 70 feet below the surface. Dive teams recovered two occupants Tuesday and the third occupant Thursday night.
Washington County Sheriff's Office
-Update on Plane Crash-
For Immediate Release
Media Contact: Commander Kyle Schenck
Date: 09/15/2020
ICR Number: WC20041232
The Washington County Sheriff's Office, with assistance from the Cottage Grove Police Department, Hennepin and Dakota Sheriff's Office Dive Teams, recovered two of the three occupants onboard the aircraft.
Press Release Prepared By: Cmdr. Kyle Schenck
The bodies of two of the three people onboard a plane that crashed on Grey Cloud Island in south Washington County on Sunday have been recovered.
The bodies were recovered on Tuesday from a water-filled quarry by divers from local law enforcement agencies. Names of those who died will not be released until next of kin have been notified, according to the Washington County Sheriff’s Office.
A statement by the agency stated that “search conditions continue to be difficult due to the depth (of the water) and debris from the wreckage.”
Three people were in the Cessna 172I Skyhawk aircraft when it left Fleming Field Municipal Airport in South St. Paul sometime after 2 p.m. Sunday. Officials were notified that the plane was missing 8 p.m. Sunday night and found the first sign of wreckage — a tire from the airplane — three hours later in the gravel-rock pit on Lower Grey Cloud Island in Cottage Grove. The pit is operated by Aggregate Industries.
According to FlightAware.com, a service that tracks flights, a Cessna Skyhawk took off from Fleming Field at 2:28 p.m. It was last seen four minutes later.
The Washington County Sheriff’s Office, with assistance from the Cottage Grove Police Department and the Hennepin County and Dakota County Sheriff’s Office Dive Teams, are working at the scene.
The incident is still under investigation with assistance from the Ramsey County Medical Examiner’s Office and the Federal Aviation Administration, the sheriff’s office said.
https://www.twincities.com
-Update on Plane Crash-
For Immediate Release
Media Contact: Commander Kyle Schenck
Date: 09/15/2020
ICR Number: WC20041232
The Washington County Sheriff's Office, with assistance from the Cottage Grove Police Department, Hennepin and Dakota Sheriff's Office Dive Teams, recovered two of the three occupants onboard the aircraft.
Search conditions continue to be difficult due to the depth and debris from the wreckage.
Identification information will not be provided until next of kin notifications have been completed.
The incident is still under investigation with assistance from the Ramsey County Medical Examiner's Office and the Federal Aviation Administration.
No additional information available at this time.
Press Release Prepared By: Cmdr. Kyle Schenck
The bodies were recovered on Tuesday from a water-filled quarry by divers from local law enforcement agencies. Names of those who died will not be released until next of kin have been notified, according to the Washington County Sheriff’s Office.
A statement by the agency stated that “search conditions continue to be difficult due to the depth (of the water) and debris from the wreckage.”
Three people were in the Cessna 172I Skyhawk aircraft when it left Fleming Field Municipal Airport in South St. Paul sometime after 2 p.m. Sunday. Officials were notified that the plane was missing 8 p.m. Sunday night and found the first sign of wreckage — a tire from the airplane — three hours later in the gravel-rock pit on Lower Grey Cloud Island in Cottage Grove. The pit is operated by Aggregate Industries.
According to FlightAware.com, a service that tracks flights, a Cessna Skyhawk took off from Fleming Field at 2:28 p.m. It was last seen four minutes later.
The Washington County Sheriff’s Office, with assistance from the Cottage Grove Police Department and the Hennepin County and Dakota County Sheriff’s Office Dive Teams, are working at the scene.
The incident is still under investigation with assistance from the Ramsey County Medical Examiner’s Office and the Federal Aviation Administration, the sheriff’s office said.
https://www.twincities.com
This accident, combined with it's past known flight history, makes no sense at all. https://flightaware.com/live/flight/N8488L
ReplyDeletePilot incapacitation, suicide, aircraft upset, structural failure...we aren't reinventing ways to crash.
DeleteFlight history of the prior two weeks looks like the 172 does rental or flight school duty. That LLC has four aircraft and leasing is a common practice used by schools and FBO's.
ReplyDeleteThat FlightAware track for 13 September only shows a four minute period where the ADS-B signal was detected by a ground receiver. Can't interpret the accident circumstances from that brief glimpse.
The NTSB Factual Report and Docket were just released on this one:
ReplyDeletehttps://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/101964/pdf
https://data.ntsb.gov/Docket?ProjectID=101964
According to the operator, the accident flight was a “discovery flight” arranged by the passenger for his girlfriend. Discovery flights typically included 1/2 hour of ground training and a preflight inspection of the airplane, followed by the flight, during which the front-seat passenger operated the controls to the extent possible. The male passenger was seated in the right rear seat, the female passenger was seated in the left front seat, and the flight instructor was seated in the right front seat.
According to Automatic Dependent Surveillance-Broadcast (ADS-B) data, the airplane departed about 1428 and proceeded southbound until it crossed the Mississippi River, then it turned to a southeast heading. The last return from the airplane was at 1432, over Lower Grey Cloud Island at an altitude of about 1,900 ft and speed of 101 mph. The flight profile view revealed a sharp descent followed by a sharp ascent as the airplane approached Lower Grey Cloud Island; the airplane subsequently entered a steep descent that continued until impact. An aircraft performance study based on the ADS-B information indicated that the airplane lost over 1,000 ft of altitude in seven seconds: a descent rate of over 8,000 ft per minute, before impact.
This accident is a real head scratcher. Normal takeoff and climb out in good weather, CFI at the controls, then a sudden quick plummet straight down. A medical issue/pilot incapacitation is unlikely as you have to intentionally push down pretty hard to get a plane to dive like that when it is trimmed for cruise/climb. Pilot suicide also seems extremely unlikely - why take 2 innocent people with you when you could easily do it on a solo flight. Maybe some airframe issue, but so far no evidence was found of that.
An article with additional personal details on the victims of this tragic crash: https://www.twincities.com/2020/09/21/third-victim-from-fatal-plane-crash-idd/
ReplyDeleteStructural failure. People don't want to talk about this but we are talking about planes made from the 50's - 80's.
ReplyDeleteThis type of straight down plunge is similar to the N4765N C182 crash in Hackberry, Louisiana. In that accident, the difficulty in explaining what transpired prompted invention of a crackpot theory.
ReplyDeletehttp://www.kathrynsreport.com/2021/02/cessna-182q-skylane-ii-n4765n-fatal.html
Yes, this is eerily similar to the Hackberry crash.
DeleteVanilla Cessnas straight down out of the sky in good VFR daytime conditions. Wonder if we'll ever know.
@rcsfca - We don't know yet probably because of extreme wreckage fragmentation. The control continuity verification reported in these seemingly no elevator control/streamlined elevator dives where wings stay level (no roll) may rely solely on making sure that overload/broomstraw separation of the control cables has occurred. That's what we see stated in the reports.
DeleteObserving overload separation of the cables attached to the forward elevator bellcrank doesn't tell you if the yoke to push-pull rod to forward elevator bellcrank under the front floor portion of the mechanism train was proper before the plunge.
Extreme fragmentation makes it difficult to gather up and evaluate those destroyed mechanisms as an assembly but wire ropes can always be found and drawn out of any wreckage site. Overload separation is easy to spot, and minimum verification only requires half of each unique function identifiable cable to be found, not the full length of each cable/both sides of each separation.
If the yoke to push-pull rod to forward elevator bellcrank parts train becomes disconnected by cracking/unfastening, gets loose-item FOD-blocked or seizes, the extreme fragmentation of high speed impacts may be preventing detecting the initiating condition.
Not finding the problem leaves the souls who were lost under suspicion of bad motives. Sure would seem important to either report "all control yoke to forward elevator bell crank parts were evaluated and found to be unremarkable" or "could not be verified" in addition to noting overload separation of elevator cables in this type of plunge.
This is a very good insight into the how the elevator is connected to the yoke and the relevant points of failure in that system. However, if a pilot experiences a total failure of the elevator, then the other control cables/rods in the aileron and rudder systems (separate rods/cables) would not be immediately affected (presumably unless control forces were exceeded in the other systems). In that case, a pilot who has lost all command of elevator only (initially) would try anything to manoeuvre, i.e. using rudder and aileron. This is not observed on the video, it appears the aircraft is in a perfectly straight dive.
Delete...perfectly straight dive at the very end (according to the video footage).
DeleteRecovery from a vertical plunge where elevator control is lost wouldn't have been accomplished by "try anything" panic manipulation of aileron and/or rudder controls.
DeleteThe remaining control action available for pitch recovery in the event of elevator control loss is to run the elevator trim toward nose up, which works to recover if done soon enough. There were only a few seconds available to recognize and put into action a trim tab recovery.
It saddens me to hear about this crash. Airplanes do age and with that comes weakened structures which can fail without warning usually when the plane is being flown normally.
ReplyDeletehttps://skybrary.aero/articles/ageing-aircraft-structural-failure
I guess structural failure is always a possibility, but the evidence just doesn't show it. Look at the photos of the wreckage. The rudder, trim tab and both elevators are clearly still attached to the empennage. They did not separate from the aircraft pre-impact. Also, if you look at the video of the aircraft in a dive, you can see that the wings and tail are still attached and in their normal positions and that the plane was diving straight down with with no roll component nor any sort of turn or spiral. https://data.ntsb.gov/Docket/Document/docBLOB?ID=11978003&FileExtension=MP4&FileName=attachment_3_GH040023_10fps-Rel.MP4
ReplyDeleteThe plane being upright until impact is also supported by this line in the report: "the anticollision light on top of the tail was intact, consistent with the airplane being upright upon impact"
From the video as well as the wreckage, we can definitively establish that neither the wings nor tail separated from the aircraft in flight. The aircraft diving straight down with a relatively level bank angle and track is also significant. Structural failures are rarely symmetrical. Usually one side fails before the other, which would cause the plane to spiral or spin down to the earth. Asymmetric elevator forces will also cause the plane to roll, so if it was an elevator structural failure, both elevators would have to fail in the same way at the same time to cause a dive straight down with no roll component.
Similarly, the trim tab was still attached to the wreckage, but if the trim linkage had failed it would not be an issue. An untrimmed 172 is not too hard to handle, and in cruise, the trim tab is mostly flush with the elevator anyway. It's not like it's a heavily modified P51 traveling at over 400 knots where the loss of the tab could cause a dramatic upset like the 2011 Reno Air Race crash.
The point that both elevators would have to fail in the same way at the same time is correct and important to understand.
DeleteA credible cause that would result in elevators not being controlled by the pilot is for the control connection to drop it's fastening hardware under the instrument panel, resulting in the elevator becoming streamlined behind the horizontal stabilizer during the dive.
FAA training on proper inspection practices details a disconnected C182 "up" elevator control connection due to omitted cotter pin on a castellated nut from a true life incident in this document:
https://www.faasafety.gov/files/gslac/courses/content/37/561/ffp.htm
Didn’t relive that a 172 had more than one elevator. I’ll have to find the other one on mine
DeleteMaybe you don't have a 172. Note Cessna's perspective:
DeleteCessna supplemental inspection 5-10-01 is titled:
"Horizontal Stabilizer, Elevators and Attachments Inspection"
https://www.cessnaflyer.org/media/kunena/attachments/2700/SID+55-10-01+Cessna+172+1969-1976.pdf
"Maybe you don't have a 172. Note Cessna's perspective:
DeleteCessna supplemental inspection 5-10-01 is titled:
"Horizontal Stabilizer, Elevators and Attachments Inspection"
It's still ONE attached elevator, just split in two between the vertical stabilizer but still attached as ONE functioning mass flight control (that's why it only has ONE trim tab on the left elevator). Maybe you just don't know what you are talking about. MY 172P POH says this about the tail during walkaround:
"Ensure elevator and trim secure and undamaged, linkages free and unobstructed, check full and free movement of elevator"
^^Note: ELEVATOR. You've clearly never flown one. So you can sit down.
You are almost up to speed, judging from your split in two comment indicating an understanding that the elevator assembly is not a one piece part. Context of the elevator loss of control discussion that you had joined is all that you lack to understand what you were commenting on. Here is that context:
DeleteThe 1:36 PM May 6 commenter correctly asserted that for elevator structural failure, both elevators would have to fail in the same way at the same time to cause a dive straight down with no roll component.
Elevators plural is specified in the inspection document because as you now recognize, there is a LH elevator and a RH elevator, having separate part numbers, joined into one functional unit at the center bellcrank by flanges that are rivet-fastened to the torque tube on each of the two elevators.
The 1:36 PM May 6 commenter and everyone familiar with the inspection for the year model 172's covered in the document understands that asymmetric control loss of one or symmetric control loss of both of the elevators can occur if rivet integrity fails such that the torque tube on either or both of the two elevators becomes free to rotate within the flange attached to that elevator's torque tube.
Look again at Detail "F" if you haven't yet grasped that the rotational force applied by the bellcrank to the torque tube flanges of the two elevators relies on those rivets to move the elevators.
The inspection document states:
"Visually inspect the torque tube for corrosion and rivet security. Pay particular attention to the flange riveted onto the torque tube near the airplane centerline for corrosion,"
The information above should help you understand the discussion references to elevators that you replied to at 7:04 PM May 9. Whether your C172 is owned, rented or just a desktop computer simulation, nobody here feels compelled to command you to sit down for not initially comprehending the details of the design.
Funny how the ability to comment anonymously magnifies the snark factor by a factor of 10. Boys, you are both hereby assigned to detention....go see your Principal immediately.
DeleteI don't see any chord wise scratches on the propeller. The only time I've see a C172 go down in a similar fashion was when it was loaded aft of CG and in a unrecoverable stall.
ReplyDeleteSeems like high speed water impact would "hydro-form" the bends without making any scratch marks. Had to stop rotation immediately though, if there was no blade contact with nose gear strut during bend back.
DeleteStall demo gone wrong? Hard to imagine a CFI doing stalls on an intro flight but stranger things have happened. PAX suicide? Engine out, CFI unable to establish glide, leading to stall followed by pull up and accelerated stall?
ReplyDeleteImagine losing elevator control during stall recovery....
DeleteAgree with a stall demo gone bad ... Also agree as to WHY this would have been performed on a demo flight, which should never be demonstrated to a first-time Hot Seater.
DeletePossibly a left seat sudden panic by yanking the yoke full back causing a stall-spin. Look at the muscular build and size of the arms of the left seater compared to the smaller, non-muscular CFI. Possibly a failed, arm-wrestling match between a low-time CFI and the left Hot Seater.
Speculation, but nobdy will never know.
Left seat pax looks to have never flown or operated controls prior ? CFI would have to keep those inputs on a short leash. All it takes is a few excessive moves and you are out of the envelope. Very tragic ... RIP
DeleteSorry, no way the CFI was doing a stall demo at that point in the flight.
Delete1. They were barely 1,000 AGL. No CFI would demonstrate stalls at less than 2-3,000 AGL.
2. The flight profile is too fast for a power-off stall, which starts with slow flight, and doesn't show the initial full throttle climb indicative of power-on stall demonstration.
3. Discovery flights start with climbs, descents, and turns, before moving on to other maneuvers and rarely include stall demonstrations. No one starts out a discovery flight with a stall a few minutes after takeoff.
The passenger pulling back on the yoke would cause a climb and loss of speed well before an actual stall occurred, which isn't shown in the ADS-B track. As someone who has stalled many 172s, I can tell you it takes significant control force and time to get them to stall if you are at a 90 knot cruise. The CFI would have plenty of time to remedy the situation if that happened. Also, as you approach a stall at cruise, you are going to have significant left turning tendencies, so unless the CFI was putting in right rudder for the passenger, you'd see a left turn on the ADS-B track, but again we don't.
Also, there was no "spin". The track and video show a straight down descent with zero spin component.
To the comment about the "smaller, non-muscular CFI", there is no way you can tell someone's size or strength by the two photos published of the CFI. Even if you could, there are plenty of "small looking" people who can easily overpower bulkier looking people.
To the comment "Left seat pax looks to have never flown or operated controls prior", first of course they haven't, that's what a discovery flight is for, but I'm really curious what "look" the passenger has to make you come to that conclusion separate from what was reported.
the "look" has nothing to do with the passenger and everything to do with their flying experience .. which is none ... which therefore means every input that passenger makes on the controls will be their first .. ignore that at your own peril
DeleteLOL *every* discovery/intro/first flight has a passenger at the controls with zero experience, CFIs are well aware of the risks and pitfalls and are trained with a variety of techniques to mitigate them. If you look at the statistics, discovery flights rarely end badly and when they do, it is almost never something the passenger did. There are many other accidents on this site where a passenger with no experience had access to the controls, yet trained investigators aren't blaming them for the accident. It's almost always the pilot.
DeleteThere is no way for an investigator to know who had control by looking at wreckage. Even if hand-gripping had deformed the yoke that was being manipulated at impact, it isn't possible to know who had control when the initiating event began unless there is a cockpit video with visibility of who did what.
Delete"... but I'm really curious what "look" the passenger has to make you come to that conclusion separate from what was reported."
DeleteWell for me, it's the way she is grabbing the yoke with the right hand. That is NOT the side of the yoke you grab from the left seat. Not anymore than you learn how to drive a stick in a left-hand drive car with your right hand on the steering wheel.
Well first, that photo was taken a week before the crash, and second look around on YouTube and you'll see plenty of bad pilot technique like flying with both hands on the yoke. I've flown with thousands of passengers and intro students with zero experience and almost all of them are deathly afraid to touch the yoke and manipulate it with any force. I've never seen one even get close to shoving it forward with all their might and locking up. There is not a person alive who wouldn't know that's a bad idea.
DeleteOne way an investigator can determine who may have been at the controls is to look for broken thumbs. A common technique.
DeleteI'm not familiar with "discovery flights" but it would seem unlikely to me that the CFI would hand the controls over to a potential student pilot only 4 minutes after departure. I would think the CFI would fly to a designated area and climb to a safe altitude...much higher than 1,900 feet... that would allow him to regain control in the event of an incident.
ReplyDeleteThis has got to be a bird strike. I didn't see any feathers in the photos, but the tail assembly is gashed near the top like it hit something or something hit it, and there are dark stains on the right side of the vertical stabilizer as well. This is very sad accident and makes you wonder why this airplane suddenly became a lawn dart.
ReplyDeletePossibly a panic attack and frozen hands on the controls. Low-time CFI hesitating to sock the lady to get her to release.
ReplyDeleteI doubt we will ever get an answer for this crash; everything is speculation. A Cessna 172 doesn't go from straight and level to a lawn dart as quickly as this airplane did. Human intervention is what I feel is highly probable. I did some public research and social media searches last night and this is what I came up with below. Also, it's unusual that of all places in that area, it goes straight down like an arrow into the deepest water for miles??? Was that a passenger request to overfly? We will probably never know the answer to this crash.
ReplyDeleteLarry Schlichting -
12/10/1983 - Gets Married to wife Nancy.
3/28/2003 - Wife files for divorce
2004-2007 Mentally Committed with order for Neurolympic Medication - Minnesota Court Case No.: 27-MH-PR-04-343
5/8/2007 - Court order to discharge patient (Larry) Case No. 27-MH-PR-06-411
10/24/2008 - Larry and Nancy marry again
2/4/2020 - Both file for divorce again
4/25/2020 -Larry posts on his facebook page: "Y'all know I've had my hours cut and I'm looking for work, right? I really dislike posting on Facebook otherwise.." "lol. Two days per week if you call that working..."
Summer 2020 - Larry's bandmate from "Mixed Brew" passes away from cancer
9/2/2020 - Larry's mother passes away in hospice
9/10/2020 - Larry's mother's funeral
9/13/2020 - Larry dies in plane crash
Lucas Knight -
3/21/2015 - Car accident in which Lucas was extricated from vehicle and sustained serious injuries
2019 - Graduated from Minnesota State University, Mankato
Grace Addae-
Can't find anything.
Also, interestingly Larry has an entry in the Airmen database, but with no certificates or medical information:
DeleteLARRY JOHN SCHLICHTING
Airman opted-out of releasing address
Medical Information:
No Medical Information Available
Certificates
None
Normally even if you just apply to be a student pilot and never progress any further, you would at least have an entry in the airmen database for your student cert. Could his medical have been denied due to a history of mental illness and they either revoked or never approved his student pilot cert? At the very least you could say Larry had an interest in aviation if he has an entry in the database and may have known enough about flying to be dangerous, as they say. Also apparent from his Facebook is that he had an interest in RC aircraft and was a drone pilot.
Also, he posted the published photo of Grace in the cockpit of a different Cessna 172 (N739GG) than the accident aircraft (N8388L) on September 7th about a week before the accident, so the discovery flight wasn't their first time around the flight school. Maybe they stopped by a week before to sign up for the flight or take the ground portion and took a photo in one of the planes at the time?
I also followed the bread crumbs on this crash, and discovered troubling flags about the male passenger. I absolutely believe this was a murder/suicide. Male passenger was 30 years older than the female who was purportedly his girlfriend. If you look at his Facebook page, he has photos of large model aircraft that appear to be a hobby. He mentions the female is his new YouTube partner, and there will be videos coming. As you discovered, this female was one of his mother’s caretakers. It appears after his mother ended up in rehabilitative care, he felt she would be getting better, then there was a turn for the worse. My two theories are A: that the male either plotted revenge because he felt his mother was not cared for, and enticed the much younger female to be his “model” in YouTube videos in order to put himself in a position to take her life. B: That he met her while she cared for his mother and decided he wanted a relationship with her so he flaunted his material goods, but she wasn’t interested in a relationship, but agreed to doing YouTube videos only, and said something to that effect prior to the flight. For a man who already had several emotional blows, it may have been the straw that broke the camels mental health back. I feel the pilot and the female passenger were the victims of tragic circumstances involving a very unstable male passenger. The photo of her sitting in a plane prior to this, seems more of a scouting mission by the male passenger. If he indeed flew the large model planes seen on his Facebook, he had some rudimentary knowledge about flight; at the very basic level, how to keep a model plane in the air, and what could create a crash.
DeleteI live right next to the pond that this plane went down in. I heard from someone who was involved in the recovery of the aircraft that the investigators believe it was a suicide pact between the two passengers. This is one of the most bizarre things I've ever seen in my life. Why would you take an innocent person with you on your way out? This is beyond comprehension. Very very sad.
Delete"Neurolympic": ...treating and managing acute mania, agitation, bipolar disorder, Tourette syndrome, and hyperactivity...
ReplyDeleteSeems like pilot Lucas had a psycho on board. Pushover from the back seat?
If the yoke was pushed forward and kept there, the pitching toward nose down would have continued into an on-its-back loop.
DeleteThe video suggests streamlined elevator during the viewed portion of the plunge. Pushing from the back seat would have to be followed by active pull back to neutral position. Wouldn't expect a perpendicular water entry if elevator position wasn't streamlined after initial pitchover.
It takes significant forward pressure on the yoke to force a Cessna 172 trimmed for cruise into a dive like that and keep it there. It seems unlikely a slightly built back seat passenger could unbelt himself, lean forward, and keep that much forward force on the yoke while also resisting the significant G forces that would both be forcing him up against the ceiling from the dive and also towards the back of the plane from the acceleration while being completely unrestrained out of his seat. He'd also have to do all that while at the same time resisting the attacks from the CFI (and probably also his girlfriend) fighting for their lives to neutralize the suicidal passenger and force him away from the controls by any means possible.
DeleteAnother possibility, although also seemingly unlikely, would be if the back seater attempted to take out the CFI first (perhaps by choking him out from behind?) before trying to crash the plane, but again you'd assume the front seat passenger would try to stop him.
It is interesting from the report about the seat positions, which the back seater sitting directly behind the CFI: "The male passenger was seated in the right rear seat, the female passenger was seated in the left front seat, and the flight instructor was seated in the right front seat." but maybe he sat there to more easily talk to his girlfriend. I assume they determined these seated positions from where in the wreckage the bodies were found, which would tend to suggest no one unbuckled to crash the plane. If the back seater had unbuckled himself to crash the plane (which he'd have to do to reach the controls), there should be evidence in the wreckage of both rear seats being unbuckled (no stretch marks on the belt or witness marks on the latch), which isn't mentioned in the report.
Still this is just a "factual" report and not the "final" report from the NTSB, so perhaps there is still some additional evidence or analysis they plan on releasing on this one.
The rear seat passenger may have put his feet on the CFI's seat back and pushed him into the control panel. That would cause the controls to go fully down and to the scene of the impact.
DeleteThe report states: "The flight profile view revealed a sharp descent followed by a sharp ascent as the airplane approached Lower Grey Cloud Island; the airplane subsequently entered a steep descent that continued until impact." .
ReplyDeleteAssuming (speculating here) the rear passenger suicide theory. Considering the profile which was at first a "sharp descent (passenger pushing the yoke forward) followed by a sharp ascent (CFI reacting, pulling back on the yoke to restore attitude)", then a struggle in which the CFI is over-powered (and incapacitated), followed by "the airplane subsequently entered a steep descent that continued until impact."
This would explain why there was no effort to manoeuvre the aircraft out of the dive which, on the video footage, looks to be a straight dive with no intervention.
Unless all control cables were disconnected (see my earlier reply to a comment on the elevator linkages further up in the page). What is the probability of that happening? I can understand the elevator cable failing thereby disconnecting the elevator, but there is no effort to use the other control surfaces to at least try to manoeuvre in desperation to avert impending death.
Trim the tab for nose up to get out of the dive if the "up"cable is parted, faster you go, more authority the trim tab has. Trim tab was used to get back to the field for lost "up" cable in this example:
Deletehttps://www.faasafety.gov/files/gslac/courses/content/37/561/ffp.htm
Agreed. Good point as the airflow over the elevator would allow the tab, which moves in the opposite direction, to deflect the elevator. As we didn't see that here, one can only speculate that the CFI could have been incapacitated.
DeleteSeems likely one of the three committed suicide--the other two were murdered.
DeleteWow the mental history of the passenger is scary. Suicide by pilot seems a possibility. Generally such decisions are taken quickly and without any distress comms or anything it looks to me the plane was deliberately crashed especially given the unnatural plunge that a docile 172 is hard pressed to do.
ReplyDeleteBeing a CFI is probably the most dangerous job in the world if one has to teach people off the street and give rides to strangers with very limited info on their state of mind and motivations.
Strange sequence of events indeed. Here's another possibility - the two passengers (the one in the front left seat and the right rear seat) decided in mid-flight to switch positions. It would be a difficult transition but not impossible, and it would certainly have a high risk of inadvertent control jamming.
ReplyDeleteThis pilot would not have allowed it. He was very by the book, even with his friends on board.
DeleteFrom Nigeria, I'll bet. Those Nigerians constantly get into trouble around airplanes, even walking into the prop. Remember they're all coming off ox carts as their most advanced form of transportation, so airplanes are a mystery to them.
ReplyDelete