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I have always “felt” that speed brakes might increase the stall speed in a Mooney. However, never really read anything specific nor does the POH publish any stall speeds with the speed brakes deployed. So, thought I would take to the skies and do a “test” flight. I was a bit surprised and now believe I understand their effect better. Stalls in a Mooney Ovation - effect of weight and speed brakes.

We have had a few threads lately on the subject of takeoff and landing accidents, and takeoff, landing and approach techniques. I got a notice of a WINGS program with links to the most recent Nall report, which is the 2015 report. The full report breaks accidents down into categories, such as (1) takeoff and climb, (2) landing, (3) maneuvering, and (4) descent and approach. There is an AOPA Scorecard report for 2016-17, but it has totals and not the full breakdown, so it is not as useful. I recall that a few years ago there was an issue that accident cause determinations by the NTSB were not complete when the annual Nall report was coming out, so the Nall report, which used to be delayed by a year, is now delayed by two years. Looking at the '15 Nall report, the statistics are interesting and, I think, should factor in to how we fly our aircraft. (Unless specified, all the numbers are for GA fixed wing only, there are separate categories for commercial, and for rotorcraft in the report). Total GA accidents of all types 967 Takeoff and climb accidents 108 total/ 19 fatal 11% of total accidents/17.5% fatality rate Maneuvering 44 total/32 fatal 4.5% of total accidents/ 73% fatality rate Descent/Approach 43 total/15 fatal 4.5% of total accidents/ 35% fatality rate Landing 262 total/3 fatal 27% of total accidents/ 1% fatality rate The percentage of total accidents should be looked at as just a relative comparison. It depends as much on how many categories the accidents are divided into by the reporters as anything else, but when you see that, for example, takeoff and climb accounts for 11% of accidents, and descent and approach is 4.5%, you get a relative measure of which flight regime causes the most problems. Landings is the winner at 27%, the highest of all the categories, but also far and away the least likely to be fatal. The categories are broken down further, and that is the interesting part. Takeoff and climb have 8 subcategories, but of those, loss of control accounts for 40 accidents and stall or settle on takeoff accounts for 36. The others are relatively insignificant. Further, loss of control on takeoff resulted in 4 fatalities, so 10% of the time that type of accident is fatal. Stalls resulted in 9 fatalities for a 28% fatality rate. Stalls on takeoff are the biggest danger. LOC on landing results in alot of accidents, but a small fatality rate, somewhat similar to the LOC rate on takeoff although the takeoff fatality rate is higher. Maneuvering results in a moderate accident rate, but a very high fatality rate - stalls again being the major risk, causing 55% of maneuvering accidents with a very high 91% fatality rate. Descent and approach, also a moderate accident rate and what I consider to be a high fatality rate at 35%. The subcategories for descent and approach are what is interesting. There are four subcategories, (1) stalls/spins, (2) collisions, (3) deficient instrument approach procedures, and (4) loss of power. For purposes of deciding what is the safest way to conduct a standard approach and landing, you can kick out deficient instrument approach procedures and focus on the other three. The leading cause is stalls/spins, which accounted for 13 accidents, 5 of them fatal, for a fatality rate of 38%, which is uncomfortably high. Collisions were second accounting for 11 accidents, 2 fatal. And loss of power? Guess what. 9 accidents and zero fatalities. So much for the ole "tight pattern" propaganda. Tight patterns are advocated so that, in the event of an engine failure in the pattern you can "make it to the runway." But they are rarely if ever fatality. What causes pilots and their passengers to die at an uncomfortably high rate, is a stall/spin during the approach. Your odds of that happening at all are slightly higher than a loss of power, and your odds of dying from it are 35 times higher than a loss of power. The overall accident rate is down, but pilots are still the biggest cause at 73.5%. Here are links to the 2015 Report and the 2016-17 Scorecard. http://bit.ly/2JL1nxM http://bit.ly/1617GAscore In general, when you look at the accident rate for stalls during maneuvering, during takeoff and climb, and during descent and approach, the biggest risk of dying is from stalls. Fly your takeoffs, climbs, approach, and descent to avoid stalls and the fatality risk goes way down.