wabower
Touchdown! Greaser!
- Joined
- Sep 1, 2008
- Messages
- 12,013
- Display Name
Display name:
Wayne
Departures: Vx, Vy, or Zoom
- Thread starter Jay Honeck
- Start date
Jay Honeck
Touchdown! Greaser!
Down here in South Texas, cooling is always a concern -- but especially in summer.
Luckily, our -8 has an oversized oil cooler, so we don't need to worry about that parameter -- but our CHTs on these 90+ degree days can easily soar to 450 degrees if we're not careful. It's one reason a Vx departure is unwise, IMHO.
When we climb out, even in a normal, put your glareshield on the horizon full-power climb, we will have to level off at around 1500' AGL to let the temperatures stabilize. My target temp is 400. When it hits 400, I level out, and they will continue to rise for a bit, but should not exceed 425.
Once they drop back below 400, we can continue to climb at almost any angle, and the temps stay below 425. In cruise, at altitude, they will be a nice, cool 325 or so.
I flew a Pitts with a sight gauge on it today, did a climb at 85 mph Vx and the attitude was no more than 30 degrees. I pulled power to idle held the stick in the same position, and guess what...a slow smooth arc over the top. Airspeed only dropped a few MPH. Nothing close to a stall. No surprise. Vx in an RV is nowhere near 45 degrees.
Bill Watson
En-Route
Sorry for not editing the quote closely enough for you. This was the sarcastic part...I'm still not getting it. You think I don't come here to learn?
You're wrong...AGAIN.
The only reason to hang out in these groups is to learn about aviation. When that ceases to occur, you will cease to see me.
I don't see myself running out of new tidbits any time soon, though, so don't get your hopes up.
I'd think you have always wanted to be a lawyer if I didn't know better but that would be an insult to the real lawyers here.I think most pilots misuse the scientific term "stall", and apply it to many low altitude situations where "mush", or "tight parabolic arc" is more accurate.
The end results are the same.
You sir, at times, are playing games with words.
I accept you are here to learn as well as to play. The part you refuse to see, accept or take responsibility for is that you are also, by sheer force of personality, teaching. New pilots read you stuff and some will want to be like Jay. That's cool except that you are too frequently wrong, and wrong with attitude.
Maybe you don't mean to play word games. Maybe you have a hangover from all the trolls that destroyed rec.av. But if you make some spirited assertions and half a dozen of your peers on this forum start tearing it apart, consider saying less, listening more or if you get tired of learning or just can't be bothered, change the subject. But respect the sport and recognize the power of your influence.
Jay Honeck
Touchdown! Greaser!
Except that I wasn't being sarcastic. I truly believe this to be true:
I think most pilots misuse the scientific term "stall", and apply it to many low altitude situations where "mush", or "tight parabolic arc" is more accurate.
You don't, I take it?
Bill Watson
En-Route
"Tight parabolic arc" is not a recognized aviation term. "Mush" isn't a recognized aviation maneuver. "Stall" is both. What is it that you truly believe?
bbchien
Touchdown! Greaser!
WRONG, Bonzo.
V1 varies by field length, wind, temp and baro, as in , "what's V1 today?". It is the speed at which you can get the aircraft stopped, just short of the fence.
140 knots at the surface in an RV is hardly conducive to getting it stopped when the engine fails. What he doesn't realize is that the zoom opens up a new window of vulnerability. That being, taking the fence at 120 knots (which the window of hurt that you did not have before).
THIS CONCEPT DIRECTLY APPLIES TO JAY'S PERCEPTION OF SAFETY. It's V2 that is irrelevant to operation of a single. He's vulnerable for the whole last half of the runway. Maybe 2/3rds.
It's amazing how fuzzy pilots are, thinking about the abort. AMAZING.
You're pretty ignorant, Jay, and the verbalized hatred for people who have really thought this out, and ARE more knowledgeable than you is pretty appalling.JayHoneck said:Very few of the suggestions made in this thread have had any bearing on the discussion.
So tell me, if you have a 4,000 foot strip on a normal Temperature day, what is the max acceleration airspeed at which you can get it stopped and not hit the fence?
Now if you're going 140 knots 10 feet off the ground, and it quits, how far behind you was the point at which, say at 88 knots was, in which you might get it down and stopped....'cause you be dying now UNNECESSARILY.....
That is why V1 is important.
"Got V1?" It IS relevant, you just don't recognize it.
Last edited:
gismo
Touchdown! Greaser!
I'm rather skeptical about the 45° pitch attitude in a steady state climb at 75 Kt. Ignoring the slight (probably 2°-3°) difference between the pitch attitude in level flight at cruise speed vs 75KIAS, unless I've forgotten how to calculate HP you're talking in excess of 5000 FPM. And 5000 FPM in a plane weighing 1500 lbs would require more than 240 thrust HP (280-290 HP at the crankshaft) over and above the power required to maintain level flight at 75 KTAS (likely at least 60 HP). So unless your engine is seriously boosted I can't see that happening with 360 CuIn.
Last edited:
gismo
Touchdown! Greaser!
Well, technically crossing the end of the runway at 120 KIAS probably gives Jay enough energy to clear those FAA sanctioned 50' trees and remain airborne for another half to one mile so if there's a place to put it back down within that zone all he'll need is a good dose of Bob Hoover skills.
Seriously though I suggest that Jay try a "simulated" zoom takeoff above 1500 AGL with an engine cut at various points between 1500 ft prior to the zoom and halfway to 2500 AGL. He might find it "interesting".
RotorAndWing
Final Approach
- Joined
- Sep 5, 2008
- Messages
- 8,496
- Location
- Other side of the world
- Display Name
Display name:
Rotor&Wing
wabower
Touchdown! Greaser!
- Joined
- Sep 1, 2008
- Messages
- 12,013
- Display Name
Display name:
Wayne
Does this mean you think it's fair to assume that the guys at the FAA who have put the EAB on notice that they need to clean up their act might also have been following this thread and Honeck's other nonsense as well?
bbchien
Touchdown! Greaser!
"Oh they're all RV haters and don't count".
"PHYSICS doesn't apply to RVs, everyone knows that".
Jay has just made a sterling example of ignorance out of himself. All 51 hours' worth and a stopwatch. He not even looking at the right stuff. FHI, I climbed out today at 1,400 fpm. But it didn't affect safety at all- it was a Vyse.
I have met a few knowledgeable RV operators. And guess what? "No Zoom Climbs" unless they have 7000 feet ahead!
Last edited:
Jay Honeck
Touchdown! Greaser!
I was quoting others, not the FAR-AIM. Those terms are theirs from several posts back.
Nonetheless, I do believe these terms are used interchangeably by many pilots when, perhaps, they should not be. For example, if you're in a Vx climb, low to the ground, and your engine abruptly quits, if you don't push forward immediately will your plane:
1. Mush?
2. Stall?
3. Enter a tight parabolic arc?
4. Does it matter?
From a practical standpoint #4 is the correct answer, because the response to the situation is the same -- push the nose over quickly, preserve what airspeed you've got, and land straight ahead as best you can.
Unless you've got a better idea, in which case I'm all ears.
Jay Honeck
Touchdown! Greaser!
I never said V1 wasn't relevant. Why are you shouting?
Jay Honeck
Touchdown! Greaser!
7000' ahead, eh? Does that mean 7000' total runway length, or 7000' from liftoff, in which case you're talking more like 7500'.
Just curious.
Jay Honeck
Touchdown! Greaser!
Testing this was already discussed -- and discarded, by me -- earlier in this thread. It's simply too dangerous to fly such an experiment, unless we can find an old space shuttle runway to go play on.
Not to mention hard on the equipment. Tell you what: If you buy my brakes, and find me a nice, empty, 8000'+ runway, we'll go fly a few test runs.
I'm sure there's a mathematical way to figure it out to within an acceptable margin of error, but that's beyond my pay grade -- and absolutely no fun.
Jay Honeck
Touchdown! Greaser!
See your answer about 50 posts back. The deck angle probably wasn't 45 degrees at Vx. Frankly, I have no idea of the precise deck angle (it was my wife's estimate), nor is it relevant. It was mentioned only as a way to illustrate that the deck angle was extreme, resulting in zero forward visibility and discomfort for my back seat co-pilot, which is why we aborted the Vx departure test.
Not that this matters, either, but a 5000 FPM climb rate is sustainable in the -8 for maybe 10(?) seconds, when pulling +1 G (that's 2Gs, for some of you) at 140 knots. Airspeed quickly deteriorates, as does rate of climb.
A 180 HP Lycosaur engine can only do so much.
bbchien
Touchdown! Greaser!
So you're just gong to ignore the opened danger window I described. REALLY GOOD, JAY.Testing this was already discussed -- and discarded, by me -- earlier in this thread. It's simply too dangerous to fly such an experiment, unless we can find an old space shuttle runway to go play on.
Not to mention hard on the equipment. Tell you what: If you buy my brakes, and find me a nice, empty, 8000'+ runway, we'll go fly a few test runs.
I'm sure there's a mathematical way to figure it out to within an acceptable margin of error, but that's beyond my pay grade -- and absolutely no fun.
Tell you what. Why don't you use physics, and get into the max efficient least death window config. (Vy or just below) and do exactly what you say- that's the MATHEMATICAL way, instead of disregarding it while saying "show me a mathematical way". Or you can just have fun and actually be more dangerous and more exposed with your fun ZOOMs.
Do Mary a favor, and fly conservatively, Jay. Don't be a tool. We like you and want you to survive.
******
When I brought the Seneca home, and got her off the Ferry Permit, I used up the rest of two timed out TSIO 360 EB1Bs, a set of brakes and tires determining what V1 looks like. PIA tracon still remembers me as the Sunday Donut guy.
I have about 700 points on the spreadsheet. Then installed engines #3 and #4, changed by discs and brakes, and tires. And flew safely for the next 2000. Now on engines #5 & 6.
His drivel is everywhere in the 50 hour private FIGHTER pilot Air Force. It's endemic. "Those dangerous underpowered Wichita spam cans" is really instead, "those frighteningly ignorant guys cut loose with their Walter Mitty fantasies".....wayne said:
Last edited:
Jay Honeck
Touchdown! Greaser!
Yeah, I'm feeling the love.
What makes you think that I won't fly conservatively? Because I actually went out and tested several different departure techniques?
I have learned many great things about my new aircraft since starting this thread:
1. I've learned, through actual flight testing, that a zoom climb is no safer than a Vy climb, nor does it get me to pattern altitude any quicker, even though it FEELS quicker.
2. I have determined through actual flight testing that a Vx departure climb in an -8 is uncomfortable to the point where we simply won't do them for anything short of necessity.
3. I have learned, through actual flight testing, that it takes one minute to get to pattern altitude in the -8, on a 90+ degree day at sea level, which frankly surprised me. Apparently the excitement of flying the plane results in perceived time compression, because I would have swore that it was about 30 seconds before actually timing it with a stopwatch.
With regard to POA, I have also learned many things:
1. I have learned that some of the posters here who know so much about aviation are incapable of imparting that wisdom to others without cruelty and sarcasm. As God's gift to aviation, they believe that subjecting oneself to their abuse is a fair trade in exchange for their knowledge.
2. I have learned (for the thousandth time) that arguing with trolls only makes them happier and more persistent. After 20+ years in piloting groups, you would think I would remember this -- but it's like tequila. Every year or two, I have tie one on to remind myself why NOT to drink it.
3. Most posters here are fun, intelligent, well spoken (or written), and are capable of interesting, often witty repartee. They are why I am here!
All in all, a productive thread, and a great bunch of flying. YMMV.
140 at the surface though opens up the possibility of pulling for a hammerhead and landing opposite direction, or converting the sped into altitude to clear the fence and make the field ahead. There's actually a pretty cool video on up of an F-16 that ate a bird right on T/O lunching the engine that did just that, a hammerhead turn back. It would take nearly immediate reaction to a 3g pull to accomplish it, but it can be done. The first question is where do you have your energy stored and how can you most effectively use it, the next, and most important, question is, are you a reactive, accelerated thought personality in a crisis or are you a dissociative personality? That is the question whose answer will most likely dictate whether one lives or dies when the fan stops over where someone stores their energy.
bbchien
Touchdown! Greaser!
So as I raised many many posts ago, "is Jay actually Hoover?"
AN RV-8 is a delightful piston single. BUT IT IS A PISTON SINGLE fer chrissakes, and nothing more.
There is NO evidence that the RV 8 is safer than those "unsafe underpowered Wichita spam cans" as is all over the VAF board. In fact, as Wayne notes, the NTSB says it's the other way around, mostly caused by lack of understanding and ANTICS.
As for imparting wisdom without strong language, if Jay looks back, he might be capable of seeing that without it, he was no how no way going to really take a hard look at "zoom climb", I mean "just 12 seconds to pattern altitude...." in fact it took 3% longer, never mind his location relative to the departure end and LESSENED total energy from exceeding Vy. He had to trap himself into "mathematical way of calculating this"....when the mathematical way is Vy.....sigh.
We never even discussed the clearway. We never got to it. Henning brings up the "is he ACE enough to do the hammerhead?" I thinkin......"not so much." Though at 50 hours, he might be ACE.
Sadly, locally, we have a guy on our home field who thinks he's god's gift to E-AB aviation. It's a piston single, fer chrissakes, and we can't help him. The FSDO is waiting for the accident. So are we.
Last edited:
It just gets more and more baffling. Jay.....pull 2G's for 10 seconds and let me know what happens. Hint: you'll have gone thru inverted and back. And I've seen lots of aerobatics and G load talk, and I've never seen anyone but you refer to 2Gs as "+1G". BTW, "+5Gs" means 5 positive Gs. And "-5Gs" means 5 negative Gs.
Last edited:
No clue, one never knows how one will react until death is right there waving at you in the windscreen. Once you shake hands a few times in passing, you get a better idea lol.
JoseCuervo
En-Route
- Joined
- Mar 11, 2012
- Messages
- 2,868
- Display Name
Display name:
JoseCuervo
2. I have determined through actual flight testing that a Vx departure climb in an -8 is uncomfortable to the point where we simply won't do them for anything short of necessity.
.
Are you under the impression that other people do climbs at Vx for reasons other than necessity?
What makes the RV so unique in this characteristic? You do understand the purpose for VX climb don't you?
MAKG1
Touchdown! Greaser!
- Joined
- Jun 19, 2012
- Messages
- 13,411
- Location
- California central coast
- Display Name
Display name:
MAKG
At Vx. Not at faster speeds.
1700 hrs in spam cans, 60 hrs in an RV.
RotorAndWing
Final Approach
- Joined
- Sep 5, 2008
- Messages
- 8,496
- Location
- Other side of the world
- Display Name
Display name:
Rotor&Wing
I lived in Florida for 21 years in the same type of climate. If your airplane is having problems cooling on takeoff and climb out it's not the OAT but a problem under the cowl.
douglas393
Pattern Altitude
- Joined
- Nov 6, 2011
- Messages
- 1,962
- Display Name
Display name:
douglas
I was going to say the same thing, and was checking my engine data for the last two years, but got tired of checking after about going through just over three months of data(September 2012, Late June 2013, July 2013, and August 2013) which I believe are probably the hottest months in Florida. My highest CHT, which occurred always in the #2 cylinder was 402 degrees. What I did notice that it never occurred at the initial take off (up to 1500 ft agl) those temperatures were in the low 300's, but always occurred as I was leveling off to cruise altitude(4000 to 6000 agl), and had not yet leaned my mixture to the cruise settings, and once I did lean to cruise(max TIT) they dropped down to the 370 to 380 range.
KSCessnaDriver
Pattern Altitude
Not to derail the thread, but I'm not exactly sure how you're defining V1 in a piston twin. Are you seriously saying that above a certain speed, on the runway, with an engine failure, you'll continue?
wabower
Touchdown! Greaser!
- Joined
- Sep 1, 2008
- Messages
- 12,013
- Display Name
Display name:
Wayne
Why not?
KSCessnaDriver
Pattern Altitude
It's a piston twin, presumably Part 23 certificated. As such, there's no legal requirement for the airplane to climb on one engine. I can't think of a reason to have an engine fail on the runway and not abort in a piston twin.
wabower
Touchdown! Greaser!
- Joined
- Sep 1, 2008
- Messages
- 12,013
- Display Name
Display name:
Wayne
Nor can I think of any reason I'd buy a one-holer open-cockpit biplane with a 75-mile range, but evidently some do.
KSCessnaDriver
Pattern Altitude
Come on Wayne. Lets compare apples to apples. Are you saying you would seriously continue after you have an engine quit in a piston twin? Seems like a death wish to me
wabower
Touchdown! Greaser!
- Joined
- Sep 1, 2008
- Messages
- 12,013
- Display Name
Display name:
Wayne
If I didn't know more about it than you do, I might think so too. Why would it matter whether the power comes from kerosene or avgas?
denverpilot
Tied Down
Heh. Wayne's messing with you because it's doable. Think about it.
You can calculate V1 in a light twin. You just have to put heavy restrictions on your fuel and cargo load. (And up here, sometimes cancel the flight.)
See some of Doc B's posts. He flies his (fine) airplane in this manner.
It's not taught to light twin renters, being hammered through a rating, but there's no reason you can't fly them like the pros fly stuff who have lots more available engine-out thrust.
You can calculate V1 in a light twin. You just have to put heavy restrictions on your fuel and cargo load. (And up here, sometimes cancel the flight.)
See some of Doc B's posts. He flies his (fine) airplane in this manner.
It's not taught to light twin renters, being hammered through a rating, but there's no reason you can't fly them like the pros fly stuff who have lots more available engine-out thrust.
KSCessnaDriver
Pattern Altitude
It doesn't. I'm just saying that piston twins and single engine climb are not a place I want to be.
That's great. Unfortunately, as a professional, I don't get a choice on how much cargo goes on my piston twin. I'm paid to fly the airplane to its fullest extent, not pussyfoot around trying to make it safer by limiting the usefulness of the aircraft. So I fly it as the book and company opspecs say to fly it. Engine failure before rotation, we ain't flying.
Skylane81E
Final Approach
In a Seneca you are in the air before you can continue SE, however if you have enough runway you can ensure that you still have enough ahead of you to land out if that failure occurs before you can fly away OEI.
Depends on what weight you are taking off at. At my typical flying weights, I would consider it depending on speed at failure and conditions ahead as I have performed tests that show me I still have reasonable ability to climb on a single engine, and indeed proved it out in another 310 years ago that considering I had over 7000 of runway left, I should have just landed ahead after failure right after rotation. Pt 23 doesn't make any requirements for SE climb nor does it require testing for any abilities below gross weight, that does not mean the performance doesn't exist. This is where multi engine flying is more complex than single engine, you have more options which requires more thought as to which option one should choose where along the path when something happens, and all this needs to be figured before the throttles go forward.
wabower
Touchdown! Greaser!
- Joined
- Sep 1, 2008
- Messages
- 12,013
- Display Name
Display name:
Wayne
OK, Mr. Professional, at what speeds to V1 and Vr occur in whatever you're flying?
KSCessnaDriver
Pattern Altitude
V1 not published, calculated or otherwise authorized to use, so it's irrelevant. Vr, 100 knots.