A couple of pilots from Texas on a refueling stop in a snowstorm in Maine significantly overestimated how much time they had to get airborne after anti-icing before their Challenger 650 pitched up then rolled right after taking off from Bangor Airport in late January. The aircraft, with almost 20,000 pounds of fuel onboard, then exploded and all six people onboard were killed. The NTSB issued its preliminary report on Friday and at least partially confirmed speculation that had been raised since before the wreckage had cooled. The report is copied at the end of the story.
After refueling, the Challenger (technically a CL-600-2B16 but referred to as a model 650) was deiced and then about 28 gallons of anti-icing fluid was applied to the jet. About 17 minutes later it started its takeoff roll, almost twice as long as the FAA’s Holdover Time Guidelines recommended for the conditions, which were considered a moderate snowfall with a temperature of 3° F with a northeasterly breeze of 6-8 knots. According to the FAA recommendations, they should have been in the air no more than nine minutes after the start of the anti-icing application.
The aircraft, owned by a prominent legal firm in Houston, was on its way to Chalons en Champagne in northeastern France. As they were taxiing to Runway 33 for the transatlantic leg, the pilots discussed the anti-icing hold time and agreed that they had 14-18 minutes to get airborne and if the wait time exceeded 30 minutes they would return to the de-icing pad.
After the crash, ATC recordings reviewed by AOPA revealed that an Allegiant Airlines crew had elected to return to their gate after physically checking the wings for contamination. A Breeze Airways crew was discussing the conditions with the Allegiant crew as the Challenger prepared to head for the runway. “Yeah, my guys are trying to make us go, but I keep telling them this is stupid,” the Breeze pilot told the Allegiant pilot. The Challenger crew didn’t hear that exchange because they were on the deicing truck’s frequency.
There is always some ambiguity in holdover charts. The crew thought they were within the time period though the NTSB concluded the time was half what the crew thought. What bothers me even more is that the crew agreed to extend the time to double what they had calculated. Extremely poor decision in an aircraft that has a history of being very susceptible to icing. The FAA requires annual training on icing conditions for Challenger crews and semi- automated systems have been added to the aircraft. We keep making the same, dumb mistakes.
Didn’t a 121 flight go into the Potomac a few (I’m old, could be many) years ago for exactly the same reason? We’re supposed to study history to learn why things happened, but instead are tested on names, dates, and places.
The accident I think you are referring to (Palm Air) as I remember, was actually caused by icing of a P2 probe in the engines. Probably caused by the jet blast of the aircraft in front of them. This resulted in false power readings and the crew took off with less than the required power. Wing icing was certainly a factor and crew inexperience, especially in winter ops was a factor.
Thanks Scott, that’s the one and you naming it allowed me to go find some details on the Internet. 1982 was a while back, so thanks again for the info.
I think Air Florida….maybe.
Yes, I believe it was an old Air Florida 737 straight pipe. It clipped the 14th street bridge on the Potomac after departing Washington National Airport in DC. Most of the people drowned in the frigid waters of the Potomac river ice. One man saved several others before disappearing himself. There was a controversy between the pilots over the use of the deice equipment on takeoff before clipping the bridge. The less tactful comedians characterized that argument as “We’ll cross that bridge when we come to it.” But it is an excellent way to remember to consequences and seriousness of the accident.
Yes, couldn’t remember the airline name. Palm was the call sign.
However, there is no ambiguity to attempt a take off with ice formation on wings, especially with an aircraft known to be susceptible to any amount of ice on wings. This was a terrible loss of life and loss of an operational aircraft that should have been avoided by even the most inexperienced pilot. There is no excuse that can avoid the obvious poor decisions made by this crew.
A portion of my initial Challenger training was in cold temperatures in a real airplane with a retired factory engineering pilot as my instructor. On the descent from our first flight it became apparent we would be descending through a paper thin layer which we could actually see through. He activated wing anti-icing which caught me a bit by surprise because that layer would not have been one which I would normally have considered to require ice protection. When querying him about that he vociferously explained that the super critical airfoil on Challenger wings have zero tolerance for icing and that he had been upside down more than once in Challengers during ice shapes test flying. I became a believer in the importance of ice protection on super critical wings that day.
The “Old Bull” 😂
Having spent ~ 8 years flying into and out of at this airport, this accident puzzles me. A pilots no-go decision certainly includes no invitation for discussion. Plenty of times refusing flights or pushing departure times due to weather.
By definition there where only professional pilots and ATC involved and I can’t wrap my head around why nobody felt it was appropriate to let the Challenger crew know about the two scheduled carriers finding ways to stay put.
“My guys are trying to make us go…” sounds like a dispatcher who will slurp his coffee and bite into a cookie while you, your crew and your pax meet their maker. If the type is extra sensitive with ice accumulation and go-times after deicing, then this needs to be emphasized more strongly in type specific training.
If the type is extra sensitive with ice accumulation and go-times after deicing, then this needs to be emphasized more strongly in type specific training.
There is! Also, required annual training.
It’s interesting to note that the METAR was calling “light snow” but Table 54 in the HOT guidelines (figure 4 in the report) makes the combination of 3/4sm visibility at night with -16C temperature “moderate” snow for computing holdover time. When you go into Table 38 for computing holdover time with this fluid (figure 5 in the report), light versus moderate snow is the difference between 9-30 minutes with light snow and 2-9 minutes with moderate snow. The Captain indicated he would knock it off and go back for more deicing after 30 minutes. Wonder which column in Table 38 he was using…
Or if you entered the table with 16* F you would likewise have 0:40-1:15 with moderate snow.
Former 121 pilot and 135 indoc instructor and in Lear 60. It was drilled into us in 121 school that aircraft with “hard” leading edges (i.e. no leading edge devices) were more susceptible to icing loss of performance issues than aircraft with slats and/or krueger flaps. My 135 operation also had Challengers and Gulfstreams, we warned all our crews about the proper use of the HOT tables and the need to conduct visual contamination inspections prior to departure. If this crew was operating Part 91 as it appears, did they even have the current tables onboard?
Seeking cause? Start with the basics; Knowledge, Skills, Attitude. Had the crew recieve effective training on operating in cold weather? Were they proficient in interpreting and applying the guidance material and limitations available? Were they confident that their Knowledge and Skill was sufficient to make a sound decision? Answering NO to any of these wil lead to root cause.
That airplane would have climbed away fine and all would have had a good time in France if they had not rotated at the minimum edge of book numbers in far from ideal weather conditions. If you are going to make the decision to go, make the decision to use all the runway. There was plenty of it. Max tire rotation speed becomes Vr with any possibility of airframe contamination.
A longer takeoff run and more speed might indeed have gotten him airborne, but would you want to return with all that ice and a heavy airplane full of fuel in an emergency? And that ice was likely not all at the heated leading edges of an airplane that was departing cold air for even colder air. Would it have all safely sublimated off of the airplane in time to land in France? And then there the degradation of climb capabilities for an airplane that needs to cross the Atlantic where cold temperatures at altitude may be well above ISA which would further degrade climb capabilities over water.
And that’s not the first Challenger that has rolled over on takeoff due to ice.
Until I became a tower supervisor finally at an airport that had ice and snow (BNA), I had no idea of the time requirements to leave the wash rack for the runway. I had to start thinking of getting those de iced out quickly. EDCTs for them were disregarded in order to hustle them out for takeoff.
The FAR’s are clear. It is the pilot’s responsibility to assure that all flight control surfaces are free and clear of ice before takeoff. The current system has serious flaws though. Besides the expensive nature of deicing and the damage it does to aircraft paint and bleed air/environmental and pitot static systems.
1, Pilots are expected to stay in their seats without getting out and checking to make sure the deice crew did their job of ice removal. This is expected in non airline environments.
2.Deice crews at many locations do not practice their trade most days of the year, even at airports where cold weather is common. Often it boils down to whoever is on duty on the ramp being called to deice airplanes among other duties.
3.Communication with deice crews can be difficult at best. Some have a radio frequency to talk to pilots after the fluid type has been specified at the FBO. Airlines have their own methods, but the pilot still doesn’t get out at the end of the runway to check.
4.Pilots cannot be sure that fluid types are properly mixed and used or heated to the proper temperature.
5.Different aircraft models and shapes require different spray angles for effective deicing and this can be exponentially more difficult at night and low light conditions. Often the pilot is expected to put complete trust in deice crews who are less than qualified to do the job.
In what FAA regulation did you find this information:
, Pilots are expected to stay in their seats without getting out and checking to make sure the deice crew did their job of ice removal. This is expected in non airline environments.
So that there is no misunderstanding, let me repeat my first paragraph in order to point out the contrast I was attempting to make between Federal Aviation Regulations and everyday, actual operating expectations. To be clear, my point is that expectations are very different than regulations. Therein lies the conflict. In my career, I have yet to see an airline pilot waiting for takeoff at the end of the runway, shut down engines, get out of his seat and walk around the airplane in the snow to verify proper deice procedures.
”The FAR’s are clear. It is the pilot’s responsibility to assure that all flight control surfaces are free and clear of ice before takeoff. The current system has serious flaws though.”
According to Juan Brown the aircraft was rotated to a higher AOA than standard or necessary on takeoff, which combined with contaminated wings resulted in a stall. Crew also chose to use 85% engine power instead of full TO power. Lots of issues here. And very important lessons.