2021 TO DATE:

So far, up through the end of July this year, there have now been 3 fatal accidents in Arizona, the one out by Williams (KCMR), with 2 fatalities, the second one over by Holbrook, and the 3rd one just recently as covered below. As I write this, very little is known about the cause of the crashes.

I am saddened to report the loss of a good friend, and a friend to many of us in APA and the FAASTeam, in an accident out near Wikieup, AZ. Matt Miller, fellow CFII out of Mesa/Falcon Field, along with a highly respected fire-fighter and spotter, perished in an accident while working as a fire-fighting Tactical C-90 King Air pilot supporting the fire fighters battling one of the forest fires. I had just talked to Matt a couple of days before the accident when he was up here in Flagstaff. He will be missed by many of us. He voluntarily chose to put his skills and his life to protect others, a very noble thing to do. Also perishing in the crash was a highly respected professional fire fighter and former Fire chief from Tucson, Jeff Piechura, flying as the spotter for the fires. They both certainly understood the dangers of the job, but chose service over doing nothing. All I can say is they both chose to keep striving to be the safest air attack crew one can be while fighting the good battle. They will be missed…

gaarms 2021 august king air c90 at centennial

Interestingly, as I write this, I understand a witness saw the crash and stated they saw the wing literally come off the aircraft in flight, although at this time that is unsubstantiated. I also heard Cal Fire grounded all of their C-90 King Air’s UFN, but again, this too, is unsubstantiated.

Please remember, accidents can happen to the best of us! We make mistakes, sometimes we don’t recognize the danger ahead, sometimes the danger ahead is not possible to see or avoid until it is too late, and sometimes fate is truly the hunter, and sometimes fate wins out! We will always have our share of fender-benders and emergencies, but hopefully there are no fatalities, like the crash of the Bonanza over at Chandler this month. Although the aircraft was completely consumed by fire, all 4 people on board escaped with just minor injuries! Life is good!




gaarms 2021 august kauo c172

Fred’s Perspective


Over the past several months I have been involved in an ongoing discussion about high temperature operations, i.e., operating aircraft beyond the temperature values as published in several aircraft POH’s. This is not unusual out here in Arizona, and we often see flights – airline flights – out of Phoenix scrubbed, delayed, or modified to account for the unusually high temperatures we encounter during the summer. As I understand it, once the temperatures get way up there, i.e., 113 degrees/45 degrees centigrade or hotter, there are NO performance figures in the POH’s to work with.

Our flight school C172M model POH only shows performance figures up to 20 degrees Centigrade above standard. This raises the question as to whether operation of the aircraft is “legit” or not. Well, the same issue exists for all of us GA pilots. For example, fly your C172 out to Lake Havasu or Bullhead City in the dead of summer and you have to deal with temperatures close to 120 degrees. Or fly up here in Flagstaff in August and deal with a temperature of 90 degrees/32 degrees Centigrade (which just happens to be 31 degrees Centigrade above standard temperature for an airport at 7000 feet).

Nowhere in the POH are performance figures for those levels of temperature, which raises the questions: “Can I legally fly the airplane?”, “Can I legally carry passengers?” or “Am I now in the role of a test pilot?”

gaarms 2021 august c172 cessna skyhawk

Playing the FAA’s game, what if that scenario leads to overheating and possible engine failure? What if that scenario leads to the inability to climb out of ground effect, causes you to run out of runway, or at the very worst, lead up to a loss of control scenario while trying to find a safe place to put the airplane down? Are you at fault for not adhering to the POH, or operating beyond the POH, or ignoring the POH? What would your insurance carrier say about operating your aircraft outside of the POH? Heaven forbid I damage the aircraft, but even worse, severely injure or cause the death of a passenger while operating outside of the performance parameters of the aircraft’s POH. What is my liability then?

A reader of my article, a fellow CFII, raised the issue to the FSDO, who advised us that “Tt is the responsibility of the PIC to ensure the POH is followed. Interpolation of the performance information above the listed high temperature operations is recommended.” Unfortunately, NO GUIDANCE on how to do that interpolation was provided! And, just so you follow this, interpolation means calculating between the numbers, NOT speculating beyond the numbers!

Several parties said that going beyond the POH numbers would be “extrapolation” or projecting what they think the numbers would be. And on what basis is that premise viable? One reader referred me to a Koch chart to help determine performance values, again extrapolating information beyond the POH. So, if using the Koch chart gives me “some” performance information, can I legally apply that over the POH?

gaarms 2021 august cessna 172

One of the interested parties contacted Cessna directly to discuss the issue. They reported that Cessna engineers said, “Absolutely do NOT fly outside the performance charts and there is NO interpolation, period!”

So, there you are – no definitive answer and/or conflicting answers, leaving you responsible for your decision. As the PIC, you will be held accountable for that decision and possibly left hanging both legally should someone get injured and/or by your insurance carrier for operating outside of the POH. Will you be Capt. “Sully” Sullenberger and save the day or the Captain of the Titanic, and rue the day?

Digging further into the subject of Density Altitude and the effect on aircraft, we all (should) know that high temperatures affect performance, and the higher the elevation of the airport, the worse density altitude can affect our aircraft’s performance. So, we listen to the ATIS (if one exists for the airport) or we check the temperature from the AWOS/ASOS broadcast to compare it against standard temperature for our current (airport) elevation. Do you actually know the correct standard temperature for your airport? If you do not know that number right off the top of your head, you need to go learn it – right now!

So here are some comments from actual readers of my column (and yes, there really are some) –

gaarms 2021 august cessna172

“I receive this answer from our local FSDO. At this point, the bottom line is, there are no regulatory restrictions on Part 91 operations. It is the PIC responsibility to insure the POH is followed. Interpolation of performance information above the listed high temperature operations is recommended. I would not recommend getting our legal folks involved since I’m sure it would be a wasted effort. Let’s keep it simple. The FSDO is happy.”

“I love the fact that it states, ‘It is the PIC responsibility to insure the POH is followed. Interpolation of performance information above the listed high temperature operations is recommended,’ but gives NO GUIDANCE on how that interpolation is to be done!”

“Thank you Fred. I believe that SW Region should issue a memo to aircrews what J*** and the FSDO has said. There are some stubborn CFIs here in TUS that believe that it is only the limitations that should be followed not the performance charts.”

“Ooops, forgot one thing on this issue. So, if one interpolates above 104F (40C), what does the insurance say when one becomes a test pilot of performance? I am totally against the interpolation above 40C.”

“Interesting you bring this issue up. I talked to Cessna engineers last year about this same thing. There is no interpolation after the limits of the performance charts. If one goes beyond the POH published figures, then you are a test pilot. It's very simple, Insurance payments may/will not be considered if an accident or incident occurs (when operating above /outside of) the limits stated in the POH.”

gaarms 2021 august cessna

 “As for insurance, I have spoken to two of them and they say if there is an accident and the aircraft is being flown outside the perimeters or limitations of the POH, then nada on reimbursement.”

“Well, certainly one cannot ‘interpolate’ outside the limits of the chart, as that is not what ‘interpolate’ means. A better description would be ‘extrapolate’ based on physical laws. I am not aware of any FAA regulation which a pilot would be directly violating by using a Koch chart to anticipate what that physics would imply. But am I missing some? I think in terms of insurance payments, it would depend on the particular wording of the policy. Are you thinking of some particular language? I was just quickly scanning my policy, and that language is pretty hard to understand!”

“So, in an effort to get further information for Fred to put in his column, I both reviewed my insurance for my powered plane and called my Insurance agent who has been in the business quite a few years and obtained input from him. His staff also checked with the carrier Global Aerospace. Their conclusion was that there is no exclusion for operating outside the range of the tables in the POH. Thus, if I were summarizing I think I would say:

The Koch chart can be used to extrapolate performance outside the tables provided by the manufacturer. If combined with appropriate safety margins, this can provide a reasonable safe guideline for operation. There is no FAA regulation against doing so. Insurance generally does not exclude doing so. Anyway, that would be my summary in answer to Fred’s query. That is not to say that in Arizona there are not many situations where taking off is unwise and lies outside the tables provided in the POH; however, I suspect they would be revealed by a close examination of the POH and Koch chart.”

gaarms 2021 august palmbeach

“I believe that Sky Harbor has temp sensors along the runway. I have asked for runway temps before and were given them but only at very large airports. Perhaps the FAA runway people should start thinking about this because of change in weather patterns which make the runway hotter.”

This comment piqued my interest, so I sent this to the Phoenix ATC folks:

“Quick question – does Sky Harbor have temperature sensors in, on, or along the edges of the runway to measure and report runway temperatures? I am doing a little research into the Delta between AWOS/ASOS reported temps and actual runway temps…”

The Phoenix ATC folks responded after asking the airport OPS folks:

“That is a negative sir. Best we have is the weather station just south of Runway 7R/25L near the perimeter fence.”


gaarms 2021 august beechcraft

Their response was that they had never heard of such a system, and that they have always just used the ASOS system read outs.

So, there you have it, the Density Altitude issue simply remains an ambiguous entity. What should one do if the temperature is above the figures contained within the POH? You can’t interpolate, because interpolate means working within the numbers! So, one must extrapolate, which moves me outside of the published values contained within the POH, so can I legally do that? And what does my insurance carrier say if I operate my aircraft outside of the published number within the POH? Not to mention what will the FAA say if I operate outside of the published numbers? And then there is 91.13(a). Careless or reckless operation.

(a) Aircraft operations for the purpose of air navigation. No person may operate an aircraft in a careless or reckless manner so as to endanger the life or property of another. You know it as the FAA’s catch all “GOTCHA” FAR.

And just to close this issue out, consider this –

The ASOS/AWOS site sits in the cool (relatively speaking) grass alongside the runway, NOT on the runway. The temperature of the air over the concrete or asphalt runway is considerably hotter than the static air where the ASOS/AWOS is sitting. Look down the runway and you can literally see the heat, i.e., thermal lifting action and mirage effect, coming off the runway, so what is the real temperature in the air directly over the centerline of the runway?



Fred’s Pop Quiz…


  1. According to FAR 91.117(a), "unless otherwise authorized by the Administrator, no person may operate an aircraft below 10,000 feet MSL at an airspeed of more than 250 knots (288 mph)". Is that -
      1. 250 knots (288 mph) indicated
      2. 250 knots (288 mph) true
      3. 250 knots (288 mph) ground speed
      4. Who cares?
  2. OK, so you pack your son off to college out of state, or he decides he wants to spread his wings away from home by going to West Bygosh University for the next 4 years. He has a student pilot license. Is he required to submit a change of address to the FAA for his student certificate and how long does he have to do that?
      1. Yes, 30 days
      2. Yes, 60 days
      3. Nope, he can claim home is his permanent mailing address
  3. As part of your preflight action(s), you are required to check for the proper documentation in the aircraft. You look at the airworthiness certificate, the registration and the updated weight and balance (right?). So, does the airworthiness certificate and the registration have expiration dates?
      1. Yes and No
      2. No and yes
      3. Dunno, never really looked that close!
  4. Which incident requires an immediate notification to the nearest NTSB field office?
      1. A forced landing due to an engine failure
      2. Landing gear damage, due to a gear up or hard landing
      3. A primary flight control malfunction or failure
  5. With regard to the above question, on the downwind leg, I put the flap lever in the half flap position and the left side (pilot side) flap fails to go down. Do I now have a primary flight control failure and must I report that to the NTSB?
      1. Yes
      2. No
      3. Hmmm…. Lemme think about that…after I figure out how to land this thing with split flaps!!!
  6. One degree of ARC is considered to be 60 Nautical miles and one minute of arc is considered to be one nautical mile, and is delineated on all of our sectional charts as part of the latitude/longitude concept. Is this really true?
      1. Yes, but only if measured north-south
      2. Yes, but only if measured East- West
      3. Who cares – I just measure with my plotter
      4. Don’t care, heck I just just use my GPS for distances

See bottom of article for the correct answers.

Safety Programs

There are NOT a lot of FAASTeam safety programs on the schedule over the next couple of months all around the state, so go to WWW.FAASAFETY.GOV , click on “Seminars” and check them out for any Webinars you might be interested in. You might find one that really is right up your alley!! Should you desire a particular safety or educational program at your local airport or pilot meeting in the future (post COVID-19), like the BasicMed program or our “Winter Wonderland” snow season special, simply contact me directly at This email address is being protected from spambots. You need JavaScript enabled to view it., or call me at 410-206-3753. The Arizona Pilots Association provides the safety programs at no charge. We can also help you organize a program of your choice, and we can recommend programs that your pilot community might really like.

 Quiz answers: 1.a 2.c 3.b 4.c 5.b 6a

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