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Piper Lance crash in Nashville

Piper Lance crash in Nashville

Piper Lance crash in Nashville

(OP)
cp24.com - Five Canadians dead after small plane from Ontario crashes near Nashville

Two things, the flight profile seems odd given a spike in speed approximately 15 minutes before the crash (12 minutes before passing over the field). It's as though the engine went full throttle during the descent and then remarkably corrected to nominal. Also, another situation that struck close to home when a family was lost to pilot error, losing power and crashing after passing over the field, unable to cue up the runway on the first pass and trying to double back. Are pilots just not ready/prepared for out of ordinary approaches in adverse circumstances? I don't want to cast aspersions. I have flown but it's been too long to contemplate what would be going through ones mind when the pressure is on to stick a landing and the engine is unreliable.


Flightaware.com

RE: Piper Lance crash in Nashville

That velocity spike is just an anomaly in the data stream. There is no way a Piper could do 500mph without the wings falling off.

He has just missed the airfield on his right hand side but hasn't started the turn back before running out of height.

The report says the engine died. A 45 year old aircraft.

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

RE: Piper Lance crash in Nashville

I think one of the Kennedys died in one of them.

The turbo 6 cylinder variable pitch prop retractable under carriage light aircraft are called doctor killers for a reason.

Never flown one, I did my commercial training and test in a twin. But the people I know that did said the forced landing was extremely easy to mess up. Which is the reason why I just paid 500 more and did it in the twin.

RE: Piper Lance crash in Nashville

"Ontario" is a bit vague, but from Toronto it's about 1250km.

Range is quoted as 1750km.

Mistake on fuel has to be first check. But small aircraft crashes are often very hard to get good information on.

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

RE: Piper Lance crash in Nashville

Quote (some eye witness)

saw an airplane essentially crash out of the sky, fall out of the sky, and hit the ground at around a 45 degree angle

That, plus the trace in the first post makes me think stall-spin.

Looks like he was about 1,500 feet AGL at 3 miles out. That needs a 10:1 glide ratio. He might have made it if he kept the nose down and held best glide speed.

He certainly could have gotten to one of the farm fields on the West side of the river for a forced landing.

RE: Piper Lance crash in Nashville

I seem to remember there is a load of stuff about getting the gear down and flap out with battery power left.

They have a fairly steep glide path.

It will likely be trying to stretch the glide and stalling.

The art of slide slip to land has gone out of fashion. I agree sticky the nose down with prop spinning then flare the energy off putting the flap out



RE: Piper Lance crash in Nashville

Running out of fuel seems plausible. I don't know anything about a Piper Lance, but when I was flying Cessna 172s, I had a weight and balance issue trying to carry 3 passengers. The ground crew gave me full tanks when I requested reduced fuel. (Thankfully I caught it.) If they were running on reduced fuel to carry two adults, three children, and undoubtedly some amount of baggage, they may have done the math wrong.

RE: Piper Lance crash in Nashville

Looks like there's not much need to reduce fuel then. About 1000lbs of payload capacity once you account for usable fuel. Even with full bags (200lbs), 800lbs should be enough for two adults and 3 kids - and if you can fit three kids across that backseat they're probably light enough.

I also see in the news report where they said there was a 30ft fireball. probably wouldn't happen if the tanks were empty...

RE: Piper Lance crash in Nashville

There was always issues with that type of plane of the Engine life by date, in the UK/Europe they rarely got to the hourly life limit, it was always the 15 years or what ever it was life span.

So corrosion issues normally dictated when they came out for overhaul.

Those big turbo's had a habit of throwing a pot or the turbo going and chucking all the oil out.

They have a really long front cowling as well which restricts your forward view at best glide pitch.

RE: Piper Lance crash in Nashville

(OP)
Thanks for the responses. I agree with Littleinch that the spike is likely an anomaly. I don't recall seeing anomalies with other tracking data over the years but should have been able to figure that out.

This crash occurred just after dark and with the overlay, it can be seen that options were limited if not hopeless for an unfamiliar pilot. It would be difficult to discern the extent of the fields below and at 7:40 p.m., there would be plenty of headlights on the roads discouraging a road landing. From the data and news reports, the engine quit just after the pilot crossed the field, a very inopportune time to make adjustments. An extended glide would not seem friendly either so the freeway below may have been his only hope.


Google Maps

I'm surprised the tracking is so far off the crash location.

RE: Piper Lance crash in Nashville

Looks like there was more than one fuel tank and if one runs dry it takes a while to restart the engine.

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

RE: Piper Lance crash in Nashville

They all have more than one that big. You swap regularly so one wing doesn't get heavier than the other.

And if the engine is spinning it doesn't take very long for them to suck the fuel from the other tank and fire up again.

I suspect though it wasn't fuel starvation.

The choosing the plan is vastly more complicated at night.

RE: Piper Lance crash in Nashville

That looks like a pretty vicious turn though. The spin idea is sounding quite likely here. Especially with no power.
Bits I heard from ATC the pilot sounded very calm.

Was he trying to do a left hand circuit to land on runway 02?

The debris field is very small - either stalled and pancake landed or went in at a big angle. Not much left to sift through unfortunately.

This has a long interview with the NTSB rep https://fox17.com/news/local/single-engine-plane-c...

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

RE: Piper Lance crash in Nashville

Its not if you know what your doing. But if you haven't done it before or not been shown it its not something you would spontaneously think of.

I got shown it by my instructor for my CFI course. Who was a hairy arsed RAF pilot retired. And some of the stuff he showed me and made me do was utterly terrifying.

The turn helps you get rid of energy.

There can be other reasons for the spin. Those big engines when they seize can throw the plane extremely aggressively.

RE: Piper Lance crash in Nashville

Many times pilots have pulled up hard to try to extend the glide and stalled the plane doing so. The harder they pull the faster the descent, so they pull harder yet.

“I saw an airplane essentially crash out of the sky, fall out of the sky, and hit the ground at around a 45 degree angle,” Wiser said in a phone interview.

The angle is often misreported, but I would not expect it to be any less steep than the report. A 45 degree angle fits with a stall. If the viewer is in line the angle is often reported as straight down regardless of the actual angle.

RE: Piper Lance crash in Nashville

(OP)
CBC is drawing a direct link to an inexperienced pilot, i.e. a beneficial owner of the plane received his private pilot license less than two years ago.

RE: Piper Lance crash in Nashville

Hence the reason for the stick pusher in some aircraft.

The crash scene looks very much like a near vertical stall with very little forward velocity.

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

RE: Piper Lance crash in Nashville

(OP)
A stall doesn't arrest forward velocity, it merely retards it as gravity accelerates the downward component, hence the transition to a rapid descent. The aircraft can assume any number of orientations about its c.g. during that descent as the control and lift elements gyrate from uneven airflow over their surfaces. The trajectory however is little different than a baseball returning to earth.

Anyone with a sac of money can purchase an aircraft. Not anyone with an aircraft has the patience to develop a full skillset complete with accumin, muscle memory, flight management and contingency planning. Add complicating factors such as night flying or instrument conditions and the time investment requirements grow accordingly.

Perhaps graduated liscensing is required but that won't stop pilot error. As usual, more info will rise to the surface on this event.

RE: Piper Lance crash in Nashville

At full stall the airplane will transition to become a lawn dart as the speed is bled off from drag until it gains enough speed to transition back to level flight, unless the Earth interrupts that transition.

Unless they transition to a spiral spin, they tend to keep some forward speed, such as that on flight AF447 which pilots managed to reduce forward speed to around 124 mph with a downward speed of 123 mph but if they have enough control authority - lawn dart.

RE: Piper Lance crash in Nashville

Quote (Sym)

Anyone with a sac of money can purchase an aircraft. Not anyone with an aircraft has the patience to develop a full skillset complete with accumin, muscle memory, flight management and contingency planning. Add complicating factors such as night flying or instrument conditions and the time investment requirements grow accordingly.

Yep and its been happening for decades, which is why the term doctor killers is used.

These machines and flights are vastly more complex than the stuff we fly commercially.

I got warned very early on stay away from that crowd of "customers" quite a few wanted safety pilots with them. But realistically us PPL instructors with under 500 hours didn't have the experience, currency on type or knowledge either.

Currency is another huge factor with competency which gives the PPL instructor a slight advantage. But that's also linked to machine type.

These complex single engine, single crew do require you to be able to resemble an epileptic monkey sorting the engines out and aircraft for just a normal approach never mind an emergency.

Hence the reason why they have gone fadec engines, ballistic parachutes and the like on modern types.

Once a PPL instructor got more than 500 hours they wouldn't go near them either because they knew what the risks were and how they really weren't the aviation gods they thought they were when issued a CPL.

I wouldn't fly one, because I know I don't have the competency.

RE: Piper Lance crash in Nashville

oh just a hint.

Stop thinking of stall as speed related.....

You can be un stalled at zero airspeed and be fully stalled at V never exceed.

Its purely Angle of attack exceeding Critical angle of attack. And boundary layer separation.

And even critical angle of attack isn't set in stone, a layer of rime ice can reduce the critical angle of attack by 5 deg's in the space of seconds in icing conditions.

And all your flight control surfaces can stall its just normally its the main wings that stall first. You can get allerion, rudder and elevator stalls as well.

This time of year icing may be a factor. Both of the engine with carb ice and of the control surfaces.

This angle of attack and stall quite a few commercial pilots don't really get or buy into. They fixate on a number and don't listen or feel what the control surfaces are telling them.

RE: Piper Lance crash in Nashville

When there isn't enough dynamic pressure to produce enough lift at the maximum attached flow AoA to keep the aircraft from plummeting to the ground, then speed is related to describing the accident, and the fact that at the low speed that wing was stalled it does matter. Lift, AoA, Cl, area, A/R, airspeed, dynamic pressure,surface roughness, turbulation to energize the boundary layer, lift augmentation extensions - all work together.

In this plane all that mattered was lack of airspeed due to lack of thrust to overcome drag and the aerodynamic reactions from that.

More photos and it looks like a pancake crash rather than lawn dart. See https://aviation-safety.net/wikibase/352204

That fits with the following:

It appears to be a t-tail version, which the Wikipedia article, sourced apparently from a Buyers guide, says:

Quote:

PA-32RT-300 (1978–1979)
After the first half of 1978, Piper modified the tail to a "T" design with the stabilator (horizontal stabilizer/elevator) moved to the top of the vertical tail. Many pilots and owners complained about the T-tail's lack of authority at low speeds

Specifically a Piper PA-32RT-300T Turbo Lance II. On typical turbocharged engines there is excess heat coming from the turbo,

Stabilator is a full flying stabilizer, no separate elevator. They have less drag from the lack of the elevator hinge gap, but they aren't very popular and neither are T-tails for small aircraft. I suppose there is more trouble sealing the inboard gap along the vertical stab or the fuselage and that the fuselage typically had an odd pinch to allow clearance for movement that is more than a typical trimmed stabilizer requires. It sure does make a plane easier to find if the pilot cannot remember where they parked.

Being ineffective the pilot is limited as to the amount of stall that can be maintained as the turbulent flow from the wing disrupts flow over the stabilator.

Ref: The Illustrated Buyer's Guide to Used Airplanes by Clarke, Bill

RE: Piper Lance crash in Nashville

Quote (3DDave)

When there isn't enough dynamic pressure to produce enough lift at the maximum attached flow AoA to keep the aircraft from plummeting to the ground, then speed is related to describing the accident, and the fact that at the low speed that wing was stalled it does matter. Lift, AoA, Cl, area, A/R, airspeed, dynamic pressure,surface roughness, turbulation to energize the boundary layer, lift augmentation extensions - all work together

This is very true and a different situation to a stall. And in that situation your best using your best angle of attack for glide

Every landing is your described situation. Although we do try not to plummet with varying levels of success.

The other time it occurs is icing, the killer is freezing rain.

RE: Piper Lance crash in Nashville

I doubt very much that every landing is like that. I don't want to fly with you if you regularly plummet. The wings during landing had better be supporting the weight of the plane until the tires are on the ground, by which point it is in post-landing operation. I have often seen auto-spoilers to keep the plane from resuming into the air after that contact.

I missed that there was freezing rain in this accident.

Do you have an explanation for the panel method for prediction of sonic and supersonic flow my co-worker in McDonnell's advanced aero department where I worked directly out of college? Part of what they were working on was the canard attachment to an F-15. Not sure why; they did build and fly it. He wrote the software and jealously guarded how it worked.

RE: Piper Lance crash in Nashville

I was being sarcastic about how successful we are as pilots on how gentle we are landing. In fact in certain conditions a greaser is actually quite dangerous and very expensive due to burning the tyres.

At the point of touch down there are several things going on.

The planes energy reference plane changes from airflow to a ground based coordinate system. The relative energy states change due to this coordinate system change.

But in essence we are setting up a drag, low powered situation where the lift is less than the weight and the energy input of the engines is less than the energy output via drag and the other energy outs.

The difference between your lift and the weight is the variable which effects the rate of decent on touch down. because of the coordinate reference change I suspect the engineering maths is rather complicated as its a 3D dynamic system.

I am not sure if freezing rain is involved. But freezing rain is an absolute killer of aircraft be they light aircraft or specialist hurricane penetration aircraft. As pilots we just don't mess with it. I know a couple that have and survived and one of them hasn't flown again since.

The other one landed in Helsinki with max RPM, max torque, clean flaps with gear down at just above the stall and he had absolutely zero control left he hit the ground at the vertical speed he was doing which was 650 ft/min. We worked out he had picked up over 3 tons of ice in the space of 2 minutes, and landed 2.5 tons over max landing weight BAe agreed with our calcs. But surprisingly it passed all the inspections. It took 3 days in a heated hanger to get rid of the ice and inspected to get a release from BAe. They had to NDT all the gear and main spar.



RE: Piper Lance crash in Nashville

zero clue about that, the only aerospace engineering I did FEA was critical crack lengths in load bearing brackets and beams.

I do have above average tendency's of working out effect and cause of various things the aircraft do and being able to interpret the theory into something your average line pilot can grasp.

But the hard core aerodynamic stuff truth be told not many at the OEM's have a full grasp of what's going on. Especially when you start talking about transonic.

Not many have a clue what happens when a wheel touches the ground either. Tyres are one of the most abused systems on an aircraft. I utterly respect them for what they have to do. Most just see them as things you kick and expect to work every landing and taxing however much abuse gets inflicted on them

RE: Piper Lance crash in Nashville

I have just pulled the METAR for KJWN · John C Tune Airport

METAR KJWN 050555Z AUTO 19005KT 10SM SCT036 BKN042 17/14 A2998 RMK AO2

It won't be icing related or freezing rain.

RE: Piper Lance crash in Nashville

I didn't notice the time.

At 19:30 the farm fields that could have offered a good choice would be black unknown

RE: Piper Lance crash in Nashville

I can't really emphasize how complex handling one of these machines is when everything is working never mind when something isn't.

Add in screaming kids and family scared it would be absolutely hell.

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