The pilot reported that he was maneuvering to land at the airport in Granby, Colorado, in mountainous terrain with a field elevation of 8,203 feet mean sea level (MSL).
As he maneuvered to the east-southeast of the airport over rising terrain, he received a warning from the Columbia 400’s avionics that he was 500 feet above ground level and two additional warnings for him to “pull up.”
The pilot reported that the airplane began to gain altitude and increase in performance. He then pitched the airplane down and selected full flaps.
He reported that his airspeed was in the “150s.”
Of note, the maximum airspeed with flaps extended is 117 knots indicated airspeed (KIAS).
The pilot continued with the approach and at the runway 1,000 foot mark, the airspeed was 130 knots. At the runway 2,000 foot mark, the airspeed was greater than 100 knots. The landing speed with flaps in the landing position is 85 to 90 KIAS.
When the airplane was halfway down the runway (about 2,500 feet remaining) the pilot pressed the go-around button and advanced the throttle halfway for about two seconds before he advanced the throttle full forward.
The engine did not respond, so he checked the mixture and propeller controls and then examined the engine page on his digital display. When he looked outside the cockpit, the airplane had drifted to the right of the runway and continued to drift.
The airplane stalled and then landed hard.
The pilot reported that he thought he “experienced a wind shear situation” on landing.
The airplane sustained substantial damage to the forward fuselage.
The calculated density altitude at the time of the accident was 10,743 feet. The airplane was loaded with three passengers for a weight of about 3,250 pounds.
The combination of weight and density altitude would have affected the airplane’s ability to climb as expected by the pilot.
The recommended visual pattern when arriving from the south involved flying above the midpoint of the runway to the north and make a pattern to land, to avoid overflying high terrain and noise abatement areas.
The pilot reported that in the preceding two years, he regularly operated out of airfields around 4,000 foot MSL.
Probable Cause: The pilot’s loss of control during landing in high density altitude conditions.
To download the final report. Click here. This will trigger a PDF download to your device.
This August 2021 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.
First and foremost………. it was NOT, not,.. a HIGH-Density situation………… it was a LOW-density situation……….. resulting in the aircraft and the pilot having to perform as those they were higher in altitude than they actually were……. The FAA and everyone needs to just state DENSITY….. not high or low….. and once the calculation is done it is obvious what the problem will be…….. a decline in performance……… or an increase
NOT ENOUGH AIR OR OXYGEN…… BEP-W…… as compared to seal level standards, which all aircraft are referenced back to….
Our atmosphere is about 78% of nitrogen and 21% Oxygen at sea level…
BEP-W
Brain…… needs oxygen
Engine… needs oxygen
Propeller… needs to move something… in this case air… propeller does not care of oxygen
Wing…… again… wing does not care about oxygen… it needs to move something
H-H-H
High in altitude,
High in Humidity..
High in temperature
All will impact the performance of your aircraft…….. how much is what you are supposed to calculate each time you fly and then decide the best course of action for those conditions:
Be a subject matter expert on the aircraft you are flying, that day, under those conditions… if you are not, then you are doomed to fail… maybe tomorrow, maybe 10 years from now……
Bottom line: your job at the PIC is not to die in an aircraft….
To the non-pilot, the phrase ‘high density altitude’ can be misleading.
The phrase relates to the altitude corrected for atmospheric pressure and temperature.
In this case, the 8,200 ft elevation of the airport, when corrected for temperature and pressure, was effectively 10,700 ft, a high effective altitude due to the air density.
All of us understand the term ‘high density altitude’.
Most airport ASOS information will state the ‘density altitude’, when the temperatures are well above standard.
I flew out of Casa Grande, AZ one summer day. The airport elevation is 1,400+ ft, but with the temperature at 107 degF, the density altitude was almost 7,000 ft. , making it difficult for the old Cessna to climb at all.
I agree with my friends on ‘the panel’…
Read the pilot’s “Attached Letter”.
A 200-hour Private Pilot flying a heavyweight, high performance airplane in an unfamiliar, unforgiving environment, with apparently no regard to the concept of a “stabilized approach”.
The airplane did everything it was supposed to do; but flying at @ 5,500’ DA (similar conditions at the 4,000’ MSL airfields “he regularly operated out of”), clearly not the same as the 10,700’+ DA encountered at KGNB. Even with a TSIO-550.
The aircraft is able to climb at 1,000 fpm at 10,000 ft. , so there is no issue with a go-around.
But, I imagine that the turbos will take a few seconds to spool up to provide the boost pressure, so the pilot would need to anticipate the need to add power.
Could be: There’s a “Caution” in the “Amplified Procedures” section of the C-400 POH that says “Avoid rapid throttle movement in order to reduce manifold pressure overboost. Smooth throttle movements allow the turbochargers to keep pace with engine operating conditions.”
Pilot stated “The engine did not respond, so he checked the mixture and propeller controls and then examined the engine page on his digital display.”
There’s also lots of guidance in the Amplified Procedures section concerning leaning…depending on altitude, percent power, TIT, phase of flight, etc.
There’s nothing under “Descent”, “Normal Landing”, or “Balked Landing”, but under “Short Field Takeoffs”, it says “Be sure the mixture is properly set for takeoff if operating from a high-altitude airport”…i.e., leaned.
Then, two paragraphs later, for “Normal and Maximum Performance Climbs”, it says “The mixture should always be full rich in climbs”, with a subsequent Caution: “Do Not Lean the Engine During Climbs”. Ever.
So, it makes me wonder; where was the “red knob” when he initiated this go-around at a high altitude airport?
It was never a stable approach. 150 kts over the numbers is a reason to go around now.!!
Then he ‘pushed a button’ and the aircraft accelerated….then looking down at the glass to access the ‘engine page’.!! What was he thinking being so close to the runway.?
Again, it’s too much aircraft for a low time pilot, who apparently didn’t know the systems, or the basics of landing this aircraft. !
Sounds like he was expecting the plane and electronics to make up for his dependency and inability.
Appears nothing was working out correctly from the very beginning of the approach. That’s when the go-around should have been started.