lesuther wrote:I can't make heads or tails out of anything here. I don't have a clue what 'zoom reserve' is, let alone what "...we value enough kinetic energy of pressure airspeed to maneuver" means.

Me too. "Maximum kinetic energy pressure of airspeed", "potential gravity thrust of altitude", "zoom reserve"-- by themselves or sometimes coupled two or more together.

Wolfgang Langewiesche, in "Stick and Rudder," accurately said, "Airspeed is altitude and altitude is airspeed." I used his terms until I ran into another scientific mind (Bob Reser) that could make my unscientific mind understand this better and describe it more accurately.

Wings create lift when they have enough kinetic energy of pressure airspeed to overcome weight, drag, and such. Energy doesn't go away, it just changes. We can get kinetic energy of pressure airspeed by moving the wing forward with thrust, by rotating the wing with thrust or gravity auto rotation, by pushing forward or allowing natural descent in a turn (gravity thrust of altitude,) by taking off downhill and into the wind, by receiving free wind energy from nature in thermals and over uneven terrain, and by using the free kinetic energy enhancement of ground effect.

Because our industry has been pushing integration of instrument reference flying with contact flying many years now, we tend to think of only engine power (thrust) as a source of this necessary kinetic energy. When we fly low power to weight airplanes with heavy weight loads from stuff in the airplane, load factor in a level turn, or high density altitude, we begin to experience power (thrust) problems. In instrument flight and high contact flight we can deal with these problems by limiting maneuvering. In mountain work and other low level work, low power to weight pilots have to look elsewhere for energy. We have to manage all energy.

Think of a simple instrument turn. If we have no visual horizon, we need to keep the rate of turn needle near the dog house. We need to have a DG heading to turn to. We need to add a little power to replace the lift lost in the bank. We need to control altitude with engine power. We need to control airspeed with pitch changes.

Think of a simple contact turn. We have decided to go down that road to the right. We have a visual horizon. We need only to get the turn in before we have flown or drifted to far to get our turn in before things on the ground cause us to want to have our wings level again. We could add the power to replace the lift lost in the bank, but that would increase the rate of turn causing us to have to bank steeper. We could hold altitude with elevator, but that creates more load factor and can get dangerous. We are already going too fast at cruise. We need to just manage the energy available. Rather than add power to stay level and increase both load factor and rate of turn, why not pull up wings level to trade airspeed for altitude? Now we can turn to the target at whatever bank is necessary while allowing the nose to fall through naturally. We are now trading that gained altitude for airspeed (the energy did not go away.) We simply roll out on target, leveling the wings before pulling up, and pull up trading airspeed for altitude (the energy did not go away.) We are now going over the road at the original altitude. I call this turn, "the energy management, no load factor turn."

I have to be honest here. When I first started reading your posts Contact I thought "who is this guy anyhow?" All this info and new interesting threads as a newbie...hmmm

Now I am thinking that MTV may have just very well met his match here. I very much am enjoying your posts. MTV's as well of course. Thanks for the time spent! Just please keep it in lamens terms for those of us that will never be an aeronautical engineer or brain surgeon ... as you did in your last post.

AKT

AKT-It is obvious from the posts that MTV and Cary are good instructors. Rob is a good instructor who has spray experience as well, so he is familiar with these techniques. Many fly this way but don't know how to describe it. Before Practical Test Standards dumbed down and standardized the various techniques of various instructors, many flew this way. Wolfgang was the only one, back then to write some of it down.

Practical Test Standards are appropriate for high work. I wish they would think a little more about takeoff and landing. There has been progress, however. The new PPL PTS calls for acceleration in ground effect to Vx or Vy as appropriate. For a crop duster, they are still giving up a lot of free ground effect energy.

Finally, I am not always right. My wife says I live with my foot in my mouth. When I read Bob Reser's book, I realized I had forgotten that you are to add power in the level turn to replace the lift lost by banking. Having worked most of my life in poorly powered junk at high density altitude at full power all the time using energy management was no excuse.

How do I hydroplaning the wheels?

Very carefully. Like formation flying, here is a place for fine motor rather than gross motor dynamic proactive control movement. If we just sit on what we have and wait for it to dig in or not, we will get wet. Not a good idea unless we really have limited gravel bar or beach space. Spraying cotton is much safer. We can just get really close using dynamic proactive fore/aft stick movement and wait for the tick, tick, tick of higher bowls hitting our tires.

aktahoe1 wrote:I have to be honest here. When I first started reading your posts Contact I thought "who is this guy anyhow?" All this info and new interesting threads as a newbie...hmmm

Now I am thinking that MTV may have just very well met his match here. I very much am enjoying your posts. MTV's as well of course. Thanks for the time spent! Just please keep it in lamens terms for those of us that will never be an aeronautical engineer or brain surgeon ... as you did in your last post.

AKT

What I like the most is that there are no emotions with his post. All periods and quotes. Not exclamaition. I guess we have no funny business here!!....!!!!!!!!!!!!!!! phew gotta make of for the lack thereof!

In Vietnam, I got shot down on my AO checkout with a Warrent called Bloody Bart. Where do you get a name like that. Bart walked around the Air Cav troop area in shower shoes...period!!!! He was loud, obnoxious, and used the term "kiss my ass" a lot.

Each Air Cav troop had ten Cobras, ten OH-6A loaches, ten UH1-H lift Hueys, and an infantry platoon made up of snake eaters (troops who had been to all the gory/glory service schools.) These snake eaters liked to use their M-79 grenade launchers with the grenades removed to shoot rats coming out of the rat box. Pull!!! Boom!!! Rat blood and guts all over the wall!!!!!!!!

In the club, Bart was losing an argument and resorted to his unual, "bite my ass." The other soldier said, "why don't you bite my favorite rat's ass." Bart walked out to the rat box, pulled out a rat, and bit his ass. No bullshit!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

contactflying wrote:In Vietnam, I got shot down on my AO checkout with a Warrent called Bloody Bart. Where do you get a name like that. Bart walked around the Air Cav troop area in shower shoes...period!!!! He was loud, obnoxious, and used the term "kiss my ass" a lot.

Each Air Cav troop had ten Cobras, ten OH-6A loaches, ten UH1-H lift Hueys, and an infantry platoon made up of snake eaters (troops who had been to all the gory/glory service schools.) These snake eaters liked to use their M-79 grenade launchers with the grenades removed to shoot rats coming out of the rat box. Pull!!! Boom!!! Rat blood and guts all over the wall!!!!!!!!

In the club, Bart was losing an argument and resorted to his unual, "bite my ass." The other soldier said, "why don't you bite my favorite rat's ass." Bart walked out to the rat box, pulled out a rat, and bit his ass. No bullshit!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Now that most are familiar with my made up terminology (a former President taught me how to make up words on the fly,) I will address the Vx versus low ground effect and zoom takeoff engine failure.

Since this results in a six seconds or less event, the extra energy maneuverability and rapid transition afforded by low ground effect can make a real impact. Sure, the potential gravity thrust of an airplane at 200' and Vx can be significant as well. Energy is energy; we just need to manage it. While I have had more experience with the low ground effect technique, I have experienced the 200' at Vx with students. No engine failure but I have screamed "nose down " and even taken the controls on occasion. I would have enjoyed teaching the Vx method more had approved texts and instructors like MTV had yelled, "try to hit the tree. "

One of the problems with low level and immediate post takeoff engine failures is that they are very hard and potentially dangerous to simulate.

During one recurrent checkride, I was taking off in a Cessna 185 on floats out of a relatively small lake, amongst a bunch of small lakes. The check airman let me get to about seventy feet ago, then pulled the mixture to idle cutoff. I was guarding the throttle..... I pushed hard, flared and landed....the only option. Fortunately, there was another small lake right there, and we landed on it.

First thing I thought was: How big a mess would this .40 cal. Sig under my left arm make if I plugged the dumb ass to my right with it. Restraint prevailed, however....

I then informed the guy that I would drop him off on shore, because this was a really tight lake. He could walk around to a larger lake, and I MAY consider picking him up. A thirty mile walk to town was likely on his mind. The lake we were in was indeed big enough for a circling takeoff, but I had no intention of giving him that one, and wanted him wondering if I'd actually pick him up.

I did, but told him he was to sit in back...the checkride was over, and I had no intention of affording him access to the controls.

We flew back to town, he started doing the paperwork for the checkride, and I told him the checkride wasn't over. I called our Aviation Manager and told him I was filing a Safecon, I still needed a checkride, and I'd never take a checkride from that gent again. And I didn't.

Ac ually, I was kinda proud that I hadn't shot the dumbass.

The point is, that's a great way to break airplanes and hurt people.

Simulation at altitude is fine, but it doesn't have that fine edge to it. In many airplanes, and the 185 on floats is one, there is simply no time to consider options, you must act NOW if you are to succeed, and most of us take a few seconds to process, then act.

In most evolutions in aviation, a few second pause to process and select a course of action is a good idea, and no harm. But in seaplanes and other high drag craft, if an engine fails at very low level you really can't afford that time.

I credit my firearms training with helping with this, since many situations there don't offer the luxury of time.

If you have a couple hundred feet agl, you may have a little time, but if you are pitched nose up in a climb, you must get that nose down ASAP, and reduce the AOA. A stall in this scenario will almost never end well.

The Super Cub is a classic case in point. The operators handbook (there is no POH, and the flight manual is pretty thin) recommends full flaps and 45 mph as a Vx configuration in standard conditions. Power off stall speed with full flaps is listed as 42 or 43 mph, depnding on your year. Go fly a SC at 45 and full flaps, at altitude, and abruptly reduce power to idle. That should tell you ng you need to know regarding a power failure at low lwvel in a Vx climb. I don't care who you are, it's going to stall.

Now the good news: The old mantra that most engine failures occur at first power reduction after takeoff, or during full power ops have been thoroughly debunked. Most engine failures occur in cruise flight in fact. Which is the environment where our engines spend most of their time....duh.

Nevertheless, at low level, there isn't a lot of time to sort out options. Being spring loaded to a viable and survivable option will serve you well in most cases.

MTV

Good one!