I am impressed with your skill and your caution. I particularly enjoyed your reports as you flew the Titan from the East to West Coast. You are very right to be "somewhat doubtful" that a 1000 ft grass runway "provides sufficient runway for safe operations" at 6000ft. I see several "red flags" in your story. Even if 1000 ft were adequate at 6000 ft elevation for the Tornado under "normal" circumstances, it would require a good deal of judgement and pilot skill to decide when to takeoff and when to wait for a better day. Your new Tornado owner appears to be bulding skill but is no where near the point of being able to operate into and out of a short field safely at this point.
I am an old (not bold) pilot with some experience with short field operations. I grew up flying a J3 Cub out of a 900 ft sod runway in Wisconsin (about 1300 ft Elevation). I bought a Titan IIS with a Rotax 912 last summer and flew it from Knoxville TN to Little Falls MN to get it home. I love the airplane and it performs well. I am operating out of a 4000 ft hard surface runway and have flown it into a 2300 ft sod runway owned by a friend.
Once I get familiar with an airplane's performance, I use an old sliderule type device called the TakeOff Performance Computer to estimate takeoff distances for other than "normal" circumstances. The results are usually quite surprising, especially if I'm considering a short grass field. This old calculator is (C)1971 by Richard Fritz (did I mention I'm an old pilot?) This computer is still available at Sporty's Pilot Shop: Takeoff Performance Computer, Item Number: 2091A Price: $22.95. Using this handy little calcuator will give you a good (and often surprising) idea about how takeoff performance varies under a variety of conditions.
Let's assume a comfortable flying day of 60F, Sea Level Elevation, Hard Surface, No Slope, No Wind - The actual Takeoff distance will vary with how I have the prop pitched (mine is pitched for cruise - turns 5200 on takeoff with a Rotax 912 in my Titan IIS), Fuel, Passenger Load, Pilot Skill and Technique that day. So let's measure the takeoff distance and call that 100% takeoff distance. For me, that's about 600 ft.
Let's see what the Take Off Performance Computer tells us about the effect of Temperature.
100% Takeoff Distance at 60F, Sea Level, Hard Surface, No Slope, no Wind.
110% Takeoff Distance at 70F, Sea Level, Hard Surface, No Slope, no Wind.
120% Takeoff Distance at 80F, Sea Level, Hard Surface, No Slope, no Wind.
130% Takeoff Distance at 90F, Sea Level, Hard Surface, No Slope, no Wind.
So a good rule of Thumb is to add 10% to your takeoff distance for each 10F of temperature above 60F.
Now let's look at the effect of Altitude.
100% Takeoff Distance at Sea Level, 60F, Hard Surface, No Slope, no Wind.
115% Takeoff Distance at 1000ft MSL, 60F, Hard Surface, No Slope, no Wind.
140% Takeoff Distance at 2000ft MSL, 60F, Hard Surface, No Slope, no Wind.
160% Takeoff Distance at 3000ft MSL, 60F, Hard Surface, No Slope, no Wind.
185% Takeoff Distance at 4000ft MSL, 60F, Hard Surface, No Slope, no Wind.
210% Takeoff Distance at 5000ft MSL, 60F, Hard Surface, No Slope, no Wind.
230% Takeoff Distance at 6000ft MSL, 60F, Hard Surface, No Slope, no Wind.
So if you are lifting off in 600 ft (no obstacle clearance) at Sea Level, you would be lifting off at 1400 ft at 6000 ft (at 60F and everything working perfectly). Add Grass (nice short Turf) and you increase that to 1500 ft. Remember, this is where the wheels leave the ground, not when you clear the proverbial 50ft obstacle.
At 80F, 6000ft Altitude, Turf Runway (nice short grass), No Slope, No Wind, you are talking about 1700 ft required to break ground.
These results don't account for variations in engine performance, humidity, and pilot skill.
I can tell you that it's a lot different operating out of the first 1000 ft of a 4000 ft runway than operating out of a 1000 ft runway. I've done both. Add obstacles and it's a new ball game.
Can it be done? Ask Kimberly. With the right pitched prop, right loading, and Kimberly's skill, I would guess she could do it. And she would know when conditions were not good enough to try. Does your new owner have Kimberly's skill and judgement? Can it be done "Safely" on a regular basis?
I would recommend that your new owner keep the Tornado at a more adequate airport and get something like a KitFox for his 1000 ft Sod field :-)
Rob
--- In Titanaircraft@yahoogroups.com, "skyking13" <skyking13@...> wrote:
>
> As a sea level flier (Home field only 671MSL) I'm usually able to enjoy take off and landing distances of well under 1,000 feet on a hard surface runway.
>
> I recently assisted a new Tornado owner in moving his new aircraft to Montana where he is, for the time being, operating off a hard surfaced runway of more than 6,000 feet. He is a pilot, without however any recent experience and no experience in a light sport type of aircraft. He was used to flying larger GA aircraft and his most recent experience is in a Pilatus PC-12, an experience that doesn't transfer well to the Tornado.
>
> I have been assisting him with some dual and he has shown progress in his aircraft handling skills through about 8 hours of dual. He'll still need some time in doing touch and go's to become consistently proficient in landings before I'll feel comfortable about turning him loose.
>
> My question is this...He's planning (and has broken ground) on a 1,000 grass runway on his property in Montana. The location is at 6,000 feet above sea level and although this field length is enough for operations at sea level I'm somewhat doubtful that it provides sufficient runway for safe operations at that mountainous altitude. The runway has trees at one end and a river and less hospitable terrain at the other end. Do any group members have experience with measuring takeoff and landing distances at this altitude?
>
> I may of course do my own measurements from operations on the hard surfaced runway where he is currently operating and extrapolate the greater distance that the grass strip would require for safe operation.
>
> And as an aside on the hitting the tailwheel on landing. Depending on the airspeed, flap setting, and effort the pilot is putting into the flare, the tailwheel may or may not touch the runway. I've found that during maximum effort landings in the IISS...that is, looking to hit a line at the minimum possible airspeed, I'll roll my tailwheel on the runway before the mains. I've got the sight picture down pat from my hours flying the Tornado but depending on the PILOT'S ability to manage the flare the tailwheel is still there to PROTECT the tailboom.
>
> Blue Skies,
> Robert "Captain Bob" Perry
> Titan Tornado IISS 899HC
> Buellton, CA
>
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