Best Speed to Fly- Vy or Cruise Climb
Vložit
- čas přidán 26. 07. 2024
- Best Speed to Fly- Vy or Cruise Climb
The Impossible Turn series:
• Impossible Turn Series
FlyWire Store:
flywire-store.creator-spring.com
Patreon FlyWire:
/ flywire
FlyWire is about exploring flight and the freedom this incredible experience brings us on a personal level. Flying has always captured the imagination and excitement of living life to its fullest. Hi, I'm Scott Perdue. In a former life I flew the F-4 and F-15E, more recently I retired from a major airline. I've written for several aviation magazines over the years, was a consultant for RAND, the USAF, Navy, NASA as well as few others, wrote a military thriller- 'Pale Moon Rising' (still on Kindle). But mostly I like flying, or teaching flying. Some of the most fun I had was with Tom Gresham on a TV show called 'Wings to Adventure". We flew lots of different airplanes all over the country. Now with FlyWire I want to showcase the fun in flying, share the joy and freedom of flight and explore the world with you. Make sure you subscribe if you want to go along for the ride!
#Pilot #Fly #Flying #Fly yourself #aviation #FlyingTraining #LearntoFly #adventure #military aviation #aviationhistory
Website: www.flywire.online
Merch Links: flywire-store.creator-spring.com
My Book: Pale Moon Rising tinyurl.com/5abmxxkh
Twitter: @FlyWireO / flywire.online
Facebook: / flywireonline
Years ago I flew Metros. We would do a cruise climb and accept the airspeed that resulted from climbing at 1000 fpm. Generally, this gave us 180 to 200 kts ias. We did this since most of our flights were less than 30 minutes and there was no point in climbing to higher altitudes. Best climb was around 143 kts but was rarely used. Cruise climb was thus based on distance, terrain, and the available winds aloft. With strong winds aloft we would adjust our climb and altitude accordingly.
I had an engine failure coming out of Yuma. We were only going about 15 minutes down the road to El Centro so we were only climbing to 4500 ft. We lost the engine suddenly while climbing through 800 ft and 180 kts. We had departed on rw 26, so we immediately declared an emergency with the tower and requested a return to rw 08. During the turn I did a shallow chandelle ( mini yo-yo) to decrease the radius of the turn and the distance to the airport. I continued the climb during the turn to preserve energy with the airspeed decreasing to 140 kts. Once lined up with the runway and headed downhill we were able to reduce the power on the good engine and the landing was uneventful. With the extra airspeed and the resulting additional rudder authority I had absolutely no trouble controlling the adverse single engine yaw.
Scott, I appreciate your math and physics evaluations that come up with evaluations that thousands of hours of low altitude experience has taught me. Altitude is life is high altitude orientation. Airspeed is life is low altitude (and now I find out fighter) orientation. I don't want to get ahead of your schedule of videos, Scott, but I would greatly appreciate your math and physics evaluation of the basic low ground effect takeoff. I teach, on our long runways, neither Vx nor Vy is appropriate. I teach stay level in low ground effect as long as runway is still available or until cruise and then cruise climb. Listen to Scott. Airspeed gives us options. Airspeed and not altitude allowed me the maneuverability to arrive at survivable landing zones for 11 of my 13 engine failures. After only two failures was I higher than 200' AGL crop dusting or on pipelines. An extra few hundred feet, Scott can figure out how many, would only be potential energy of altitude ie. airspeed in my low altitude orientation mind. Altitude is time. My forced landings averaged six seconds from engine failure to touchdown, but I always had cruise maneuvering airspeed either coming out of the crop field or cruising on the pipeline. Only one was on takeoff. I know the free ground effect energy provided by every swath run was life saving. I know and teach the life saving energy of level in low ground effect until cruise if runway is still available. I know this free kinetic energy can be life saving. Scott can do the math to prove this I think. Thanks Scott for this video and in advance if you can tell me how low ground effect energy is actually free kinetic energy. Is this what Wolfgang meant by his advice to try to hit the tree and then zoom over?
I have read an article on zoom climb takeoffs as well as a nonloading "wingover" style turning technique written by an experienced former pipeline/crop duster pilot. From your comment on 13 low level eng fails, I believe it may be you who wrote these articles! I've been trying out the techniques with a C182T and am amazed at the amount of "free" energy gained by staying in very low ground effect followed by a zoom climbout. On longer runways, I can easily get to Vcc by the runway end. It not only feels better than dragging the plane out at Vx or even Vy, it is also fun to do and the practice has improved my landing flare control entering ground effect as well. Now, I'm wondering if this zooming takeoff technique would be better than Vx for clearing obstacles, and also if a zoom takeoff combined with the crop duster style turning technique would provide a better chance of making an "impossible" turn back to the runway. Plane in shop, so I haven't been able to go out and test a combination of these things yet, at altitude of course. That zoom article has definitely expanded my knowledge and enjoyment of flight. If you wrote these, thank you again, sir.
I’d like to read that article if you can point me to it please…
@@AaronWbirdman You will have to ask the original commenter above, Jimmy D. He is the author.
Scott can or has put you in touch with me.@@SGTSnakeUSMC
Hey Jimmydulin928 where can I read your essay on energy management?
Thanks for these vids, sir, especially relating to "impossible" turn concepts/math and flight testing in real scenarios. Valuable stuff!
I've already determined when I can make the impossible turn in my airplane. At my home airport it's wise to turn left or right at 700' AGL to avoid terrain. Flying Vy (95mph) I can make it back if I've completed that left or right turn before the engine stops.
Interesting analysis. I agree that a turn back is a BAD IDEA, but i disagree that the Vcc climb is better than a Vy climb. Here is my logic, feel free to poke holes in it!
The total energy in the aircraft increases due to work from the engine and decreases due to drag. To a first order approximation, the efficiency of the prop is constant for the speeds we are looking at. So at any given point in time, the energy added is maximised by running the engine at full power and minimising drag.
Climb rate in a light piston aircraft is related to the amount of excess power or put a different way by the speed where the difference between energy lost to drag and power from the engine is largest. As engine power is fixed (to a first order) then, this is the min drag speed.
So Vy is the min drag speed and so is the best speed to add energy to the aircraft. So climbing at Vy will always lead to being in a higher energy state at any point in time than at any other speed.
Ok, there may be good reasons not to do this, engine cooling being one, visibility over the nose another and im sure there are plenty of others. This does not change the energy argument.
Yes, at any given altitude faster is always better = more energy BUT Vy give you more energy quicker. So if engine quits after 60 seconds Vy wins, if at 1000ft Vcc wins. I dont see why altitude relates to liklihood of engine failure.
If there is a flaw in my locig please let me know. Thanks
Faster, the 'more' energy achieved by Vy is marginal. And is not convertible 1:1 to airspeed. In these tests at Vy it cost 45' altitude for each knot of airspeed gained. That negates any advantage presented by Vy. Sorry.
I can’t see over the dash of the 182 at Vx🤣😂
100% correct! KE saves lives
At Vx and less so Vy , you loss any potential advantage in gained altitude Because by the time you recognize loss of power and push over fast enough to establish best glide, you will have lost that small bit of altitude advantage. I. Addition you will not have as good control authority as you will at Vy or Vcc. In low energy climb States you will increase potential for stall or even a torque over with compete engine seizing.
I'm happy to see this perspective being thoroughly and thoughtfully presented.
There are two possible things to consider: energy state after N seconds and energy state at altitude X. The energy state after N seconds will be roughly the same (same engine power output over same amount of time) for both vy and vcc with likely vy resulting in slightly more energy from less friction at lower speed. The energy state at altitude X will have a clear winner - vcc since it simply takes longer to get to the same altitude for vcc vs vy.
The truth is that neither vy or vcc will give you enough energy for a turn back in the first 60 seconds in F33 based on your video (it’s closer to 90 secs for my A36). And it doesn’t matter which speed you are flying - you cannot turn back. Personally I usually climb to 50 feet at vx with gear down and approach flaps to get over trees and then accelerate to vcc (and cleanup) after that to keep my cylinders cooled. I accept that engine failure before I get to 2000 feet is going to result in likely airplane loss from landing straight ahead in the most open area I can see in front of me.
Well put. Another way to say it is that Vy (= ~< best glide) takes drag into account (which is proportional to v^2).
My take: If you fly the plane perfectly, that is Vy on climb then ~ < Vy (best glide) down (w/out power), you’re better off (most energy) with Vy climb. If you fly less than perfect and hesitate (or worse pull back), experience shows you’re better off climbing at some speed > Vy, and Vcc is a good compromise.
@@pedrofrigola5224 I don’t agree, my point is that energy state doesn’t change much with speed at a given time interval. If we agree that engine quits based on time and not altitude (ie failure at N sec is more likely than a failure at M sec where M > N), then it (mostly) doesn’t matter what speed you fly at for N secs. I think the lower speed / less drag effects are likely immaterial for most of the single engine planes. However, if you believe that drag is important (and don’t care about engine temperatures) then you should go with vx all the way.
@@alekseysanin Would Vx have greater induced drag than the parasite drag of Vy?
@@SGTSnakeUSMC yes , may bey ;) depends on the plane a lot. As I said, I think these effects are negligible and the energy state after N seconds doesn’t depend on speed much.
@@alekseysanin Not Vx. Cylinders damage and bird damage if you dont see them with such high nose up. And if EFATO, you might stall before the 3 seconds push down.
Very interesting. I would have never thought Vy and Vcc would be so close with Vcc giving you a material energy advantage. Valuable insight.
Excellent info… I’m following and studying you.
Most excellent, Sir. I'm a big fan of cruise climb as well!
Thanks for the discussion. I have been using Vcc more often than not for deck angle and cylinder cooling considerations. I think another benefit to Vcc is the higher airspeed gives a pilot a few more moments in the startle response before things get critical with airspeed if the engine quits.
I am a Bonanza owner as well and I always use cruise climb. I agree with all your points. I am guilty of intersection departures on long runways though. 🥵
Yes, I've learned - to take my 15 yo's exhortation: NO airplanes, Daddy! I'm no x - military jet jock, nor a retired 17k hour professional, nor even an old CFII, just a 200 hour, (over 30 years) GA guy with more dollars than sense. After watching you & J. Brown talk about death for years, I'm thinking boats, maybe....
James, we're not trying to convince you to stop flying. Just to use your head, pay attention and fly intentionally.
Well, flying is not for everyone.
ahhhh....... I ah kinda lost track at ....Vcc.... ah.......V............ would start over? NOT true, all is well and Thanks for the lesson Scott !
So simple, but it's not intuitive...which is where training comes in. Brilliant to decouple the turnback exercise from landing. We all learned about a 'hard deck' from Top Gun. Seems like a smart way to practice.
I was taught something about energy vs altitude when I flew gliders. We would practice what they called a "penetration approach" to ensure we made the runway. This involved lowering the nose, trading altitude for speed which gave us more range than min sink. We used spoilers and/or slipping to kill the excess speed once the runway was made. A penetration approach also gives you the benefit of more time in ground effect for an extra margin.
This wasn't the normal landing procedure but it was handy to have that extra option in case it was needed.
Excellent content, thirsty for more.
Flaps 1 after liftoff and at Vy will make you climb well at almost Vy FPM and also improve forward visibility and better rear cylinders cooling too. And if engine fail, flaps 1lowers the stall speed too. Flaps 1 at Vy Climbs are safer. Most engine fails are LOTOTS and they need flaps 1 WHICH ARE LIFT FLAPS. Flaps 1 at Vy.
Really, tested this have you? Factored in Startle time delays and the average Joe effect? Flaps 12/ Approach Flaps fdo indeed provide more lift... at low speeds... don't forget parasitic drag during the climb. Best Speed to Fly is largely airplane dependent. Blanket statements usually don't work well.
@@FlyWirescottperdue I learned that "Vy with Flaps 1 trick" during bush pilot training in 1996. It works well except on underpowered airplanes. Read again the post. Better cooling, visibility and safety in case of EFATO or LOTOT. If crosswind, you pop the flaps after Vr, not before.
Vcc if you are planning not to turnback from any altitude due climb angle will be flatter. You will have more energy over the Vglide speed but also farther away from the airport at that higher speed. Most engine fails are LOTOT, not total EFATO, So better practice turnarounds from the crosswind leg at 60% power and later on turnbacks if brave enough for that. LOL..
Scott, really appreciate your videos and your sharing of your knowledge,! God Bless
Great video 👍👍
Wanted to request your comments on the Dec. 7th crash of the TnFlygirl in her Beechcraft. She stated it was a "fiasco" in getting the airplane. I'm assuming she is referring to financing and insurance. I think it would be interesting for you to interview your insurance agent or even a salesman and discuss coverage and if there is any honest and frank talk about experience or lack thereof with pricing coverage. This pilot claimed to have 400 hours of flight time yet the video she produced did not seem to indicate a poor skill set. I guess I'm trying to get at if and insurer would want a check ride or would just provide a quote and be done with it. This one is quite sad after looking at some of the videos that seemed to indicate the pilot was in way over her head. Thanks, keep up the good work. Mike in Denver. Retired C-172 private pilot with 1000 hours of safe and fun hours.
I think Juan Browne did a very good review of this accident on Blancolirio. Insurance is an incentive for more/better training is an idea that hasn't been tested effectively.
Apart from a discussion about energy storage, a higher speed on climb (i.e. Vcc) is a way to store extra “TTLOC”: Time to Loss of Control (stall). An engine failure during climb will result in a rapid loss of airspeed, right down to stall speed, until and unless the pilot reduces the airplane’s pitch attitude. This necessary pilot action requires time for recognition and reaction as, all the while, airspeed is being lost. Extra speed on climb increases the time buffer prior to reaching stall speed.
A corollary of increased speed is a lower pitch attitude. Thus, if an engine does fail, the pilot will not only have more TIME, but also need less of a PITCH CHANGE to stabilize at a safe gliding speed.
Prepare your mind prior to takeoff that IF it quits...be mentally ready .. Airspeed is everything.
Maintain thy airspeed lest the earth shall rise and smite thee.
Great video. I have always had a suspicion that higher speed was better than higher altitude in energy terms due to V^2 vs. linear H. Glad to see the numbers actually back that up.
Planecrashmap website proves that almost all pilots don’t know how to use this information.
Have always used cruise climb, and will continue, speed is life.
G,day from Sydney Australia.
My learning outcomes;
* Plane performance during the climb as well as turning back (engine out) using V speeds; Vy and Vcc.
Choosing the correct technique based on the energy state of the plane and it's altitude at that time.
Thanks 🌏🇭🇲
G'day Scott,
Yay Team !
(Sighs wistfully...) It must be nice to have so much power available as to have the choice of which airspeed to climb at, to better be set up to choose between attempting to return if the the Shafting of all Crankiness runs out of Twisties...
Ultralight Motorgliders use full throttle at Best Glide Speed, and then sort of "feel around" for the highest Climb-rate on the VSI...; and then go looking for a Thermal, or some Ridge-Lift, within which to circle for a bit to wind up some
Altitude - before trying to go anywhere away from the Airfield...
Levitating on a different scale, kinda thing...(!).
Keep on keeping on,
Stay safe,
Happy Solstice Festival...!
;-p
Ciao !
If you get your helicopter add-on rating, the kinetic-potential energy curve is really drilled into your head. That's why single-engine helicopters take off much as airplanes do, unless necessary to clear an obstacle. Since at the beginning of a takeoff run, you don's have much potential energy, you have to add energy to the rotor system's "bank", which can be withdrawn in the event of an engine failure.
Woah slow down “Einstein” I am trying to take notes 😱😆
We have utilized the Vcc procedure for many. years now in a F33A. We’ve experimented with a few Vy climbs, but found these climbs to be what you have experienced. In addition, the cruise climb has afforded us cooler CHTs and better visibility. Those are big plusses operating in hot, busy Texas airspace.
Can you achieve the same FPM climb and also have the same good visibility and also more alt per mile flown with flaps Vx (flaps 12 degrees =/-) but at the Vy speed. We did that on strong Cherokees.
Thanks for the videos and all the work it takes to put them together. Gaining an understanding of the physics involved has made me a better pilot. Risk assessment and mitigation to stay safe, truly words to live by.
Rick
When i learned EFATO Turnbacks on Cherokee 140 in 1995, we used the Vglide speed which was a blue color line my Bush Pilot CFI put on airspeed indicator at the 80mph point. When under gross weight, we used a few knots under it, or almost the minimum sink speed. The problem is, the 140 is a short wing airplane, and some short wing airplanes at almost gross weight they are too close to the stalling speed with flaps up at the 45 degree bank, so we kept speed as close to Vglide Blue line to only 5mph under. And ready to push down if speed drops. My CFI had to do 2 LOTOT turnbacks for real on same Cherokee due fuel pump problems. Was the cheapest Cherokee to fly in all the region. Was old engined..
Hi Victor. Actually i had 3 LOTOTs Turnarund the airport, 2 on Cherokee 6 loaded and barelly climbing from 100 agl, and the other was on a Cessna 150, again at almost full gross. Cherokee 6 because of bad carburetor, twice. The C150 started at about 150 agl vibration, lost climbing and i felt nose down effect on elevator too. I climbed slowly to 300, dropped some flaps and returned it. Scary.
Promised myself in 1969 that I'd never fly another Cher 140.
Never broke that rule, ever.
I've flown damn near anything else.😆
@@hotrodray6802 Yes,, underpowered unles low weight and low density altitude..
Vx and Vy basically exist to accomplish a specific performance goal, clearing an obstacle. The obstacle can be virtual, like some sort of altitude constraint, but it has the same effect. Typically airplanes are flown to go from point A to B, so absent an obstacle, cruise climb speed is ideal because it gets you where you want to go more efficiently. Transport jets compute optimal climb speed for efficiency based on a lot of factors, but it is never the plane's best feet/min. If you're doing a local pleasure flight, performance doesn't really matter much as the whole flight is arbitrary. The math is interested but unnecessary.
Yes, airspeed is options as Scott says down low. Altitude, when high, is time but has only potential energy value when low. Airspeed there is life.
Vcc also gives you more thinking time before the stall is upon you.
I learned from a Bush PIlot CFI (1995) , to add some flaps like 10 degrees on every normal take off at Vr and climb with those flaps 10 degr. to 500 agl at least at Vy. Why? Better rear engine cylinders cooling due lower AOA with some flaps climbing, and also you can see better over the nose for traffic or BIRDS (1990's). I Avoided some bird strikes that way. Dan Gryder does that too lately. It is part of a Bush Pilot trick "Flaps 10 at Vr climb method". Hawks fly mostly at under 300 agl, and Geese too when doing short trips. Be able to see them. They are the biggest birds to hit and cause big damage to you. and yes, at a bit under gross weigthts we were getting ove 750 fmp of climb most times except in hot days.
IME Bush, Cessnas mostly.
wheels clear, immediate flaps up, pin Vx to 100+ AGL, Vy to clearance AGL..
I'm not a fan of the zoom climbs with flaps that you see on YT.
Thank you. Some interesting concepts to ponder. One question for the F33A with IO520, if the engine quits on climb and oil pressure is lost, what will the prop do?
It will slowly lose rpm until it is driven by the wind. This is all drag.
Most constant speed propellers will go to the flat pitch (‘high speed’) limit in the absence of oil pressure.
I certainly see how the numbers support your approach. But the numbers are always messed up by us squishy, imperfect humans. One thing I wonder about would be using some form of readily available simulator to test these approaches in more "real world" settings with real GA pilots to see if the difference we see in the numbers (more energy to work with, but at a slightly lower altitude) translates to better outcomes?
One other factor not discussed between Vy and Vcc and that's Vcc gives you better visibility over the nose (safer) and more cooling for the engine. So it better to climb at Vcc for other safety and engine factors.
I've been using CC numbers forever because the TLAR aspects just work out better. Now I see why, and it's simple physics. Also, very important to get to CC or someplace above BLUELINE for the very same reasons - more smash gives ya more options, reaction time, control effectiveness, etc..
Next video, I betcha you tell us to retract the gear ASAP. That's another TLAR technique I've been using forever. Change my mind.
Spoiler alert, I won’t even try to change your mind.
Thanks again! @flywirescottperdue, 2 questions what were the winds during your test, and did you turn into the wind?? 2nd at the end of the video you mention ADM and taking off at a 45, This has been one of my ideas when there is a crosswind component. sounds logical that if we allow the plane or even direct it down wind this would allow 180 turn back into the wind to align us with the runway. I would love to see this tested. my current take off brief involves turning into the wind if at all possible.
Craig, for this test flight the winds were very light, about 4 knots. Check out the test I did with the A36, very strong winds and I turned into the wind for that test. It helped.
I like vy for rotation. Then accelerate to cruise climb. I started out assuming that every airplane is just a glider with motors. So the first rating I got was a glider rating. I always assume that I will have engine failure some day. And then I have a very heavy glider. To me the idea of a turn around is 💯 percent dependent on altitude.
So great, Gunny. Sobering relative to how often my post runup "departure briefs" don't match reality at a given airport/runway. Too windy to fly in SoCal today so decided to do a little armchair trip using Google Maps to look closer at departure end options at the local airports I most often fly into/out of in and around KVNY. Yikes! Lots have zero options that don't end up in a building depending on the direction of flight. Can't afford a turbine but maybe it's time for that Diamond Twin...
Or a downwind departure, as ai remember for 16 you need to turn pretty quickly anyway.
@@FlyWirescottperdue My Bush Pilot CFI showed to me a 600 agl traffic pattern procedure he learned to fly in South America. Turned Crosswind at 400 agl. Much more efficient and better for engine. That 1k agl TPA is from the 40cents of Avgas prices in the 1950's. 600 agl is better.
@@outwiththem
Actually the gas prices are the same when you consider everything has also gone up $.
I've done a lot of bush flying and usually have done that. Also I've never had one quit in 50 yrs.= OCD 😳 AP/CP.
@@hotrodray6802 PAID SALARIES ARE NOT KEEPING UP.
15:06 I consulted with my 1996 CFI of Turnbacks and EFATO 4 maneuvers we did all ON THE RUNWAY, not only "at altitude". He said no way a higher speed Turnback from Vcc will be tighter or smaller radius than a lower speed from Vy turn. I will be the contrary. Vy Lower speed means tighter turn and quicker turn too when trying to pull up a bit to get the under Vglide Vmin sink speed. We made much tighter turns on Cessnas at 65 than Cherokees at 80.
Besides Vcc will put you so far away from runway that even if you turnback at VminSink, you will finish the turnback much farther away from runway. Do them on a runway and see that. Vy with some flaps climbs are better. see the other post.
I think you breezed through the video without really catching what was going on. Perhaps you should watch the other videos in the series as well. The speed loss flying Vy gets you very close to the stall speed, indeed in this video it got to within 1 knot. The speed loss at Vcc resulted in a speed very close to Vy in the first place. I appreciate you watching and thinking about it, but it seems to me your reaction was spring loaded. Watch it again and parse what was going on. You missed a lot trying to disprove me.
@@FlyWirescottperdue 3 seconds reaction time? Or more? But i will see video again. But how come such a strong engine not light single with good inertia can lose so much speed on EFATO from high speed climb Vcc.
@@outwiththem Drag....
I've done several videos on this topic, for this test I did not wait 3 seconds and I explained the reasons.
@@FlyWirescottperdue Vcc in case of NEVER TURNBACK MINDSET i think you mean.
Most engine failures are partial power, like losing one cylinder or two.
I suggest you at least try "A Turnaround the airport" after a cylinder loss, climbing at 200 fpm only, sim a full gross high alt cylinder LOTO AND LAND IT TOO.
I learned them in 1996 on Cherokee 140 at 60% power only. From 600 feet agl only on initial climb.
Hard to do, but better than crashing on top of houses and cars outside the airport.
Too many crashes on take off even if never did "A Turnback" at impossible turn conditions. Many of them are Turnaround The Airport, but many say that was "A Turnback". They are not the same maneuver.
Having some trouble following your arguments....
Yes, the Vcc v Vy is largely negligible as we're dealing with aircraft with very small power to weight ratios. It's all going to be very small differences. What you neglect to address is "what's the goal?" Am I departing in flat terrain? Mountainous? Vcc gives: better visibility, cooler engine temps, more miles behind you v time (which is the goal here, right?).
I'm not aware of any situation where a higher airspeed yielded a smaller turn radius given the same angle of bank.
Ok, hang on...Yes, Vcc may be better in terms of overall energy (K+P) BUT kinetic energy isn't the goal of Vy or Vx. You're also negating the power difference between Vx, Vy and Vcc in a fixed pitch prop engine. The F33A doesn't relate to the 172 that way as you're producing the same power at Vx, Vy and Vcc. Your THRUST is different based on prop angle. The poor guy in the 172 plays a game of RPM v airspeed.
The bottom line is teach what the current FAA standard is. Let's not reinvent the wheel based on a couple anecdotal experiences you've had. I guarantee Beech and Cessna put thousands of hours of theory and flight testing into this to come up with their numbers.
Intersection takeoff? You bet! If my balanced field allows it who cares? If it means leaving 200' of runway behind me to avoid 6 Cirruses doing 30 minutes of runup at A1 I'm going. Saving fuel and time for the boss in my game is the rule. Like I said, if balanced field allows it. I'm not going to plop my jet back on the runway at V1+30 Kts if we bag a motor lol.
Keep in mind we're training pilots to be more (sometimes not) than 172 drivers. That said, fly the airplane you're flying. Don't adopt F33A procedures into a 152 or worse, big jet technique into a SE bug smasher.
Finally, as to the "impossible turn" the pilot needs to find out what THIER turnback altitude is for their skill level and airplane. 9 times in 10, the resulting stall/spin is what kills, NOT the minimum FPM controlled off airport landing.
I'm definitely not turning back to the airport unless I have pattern altitude. Even then it's a 180 nose low and land from 1000 agl and one mile. Do able....
Enjoyed the video(s). I’ve commonly thought that 110 glide speed was optimal, but I think you are saying around 87 kn is preferable, is that what you were saying.?
Best Glide is for distance. Min Sink is for time. What do you need most in a particular situation?
I like to use short field technique as a matter of course. Off early then hold the nose over the RUNWAY and accelerate and at about 85 in the RV7-A apply back stick and see how high you can get the vertical speed to go and as it decays start nosing over. It's just a habit I learned at Purdue years ago in a glider on how we handled tow release. You pull the stick back to convert the kinetic to potential energy then from your perch you started hunting for whatever lift you could find.... I would hunt over the power plant chimney stack. The other reason though is if I do the pop up and flatten over the runway and airspeed is not accelerating I will take that as a heads up we're in trouble. I can't recommend enough folks should do initial flight training in a glider as you learn energy management and "sight picture" for landing feasibility from the get go.
Scott, if you could only employ three (3) words to describe what kills competent, reasonably experienced pilots, what would those words be?
Complacency.
Smiling. Understood.
Ty.
Always climb Vy
In a 182, I can’t see over the dash at Vx😂😅
QUESTION - I was taught in flight training that during an engine failure, airspeed above best glide should be traded for altitude with a generally hard pull-up followed by an aggressive pushover when best glide was reached. Of course not pulling so had as to create an accelerated stall situation. Here is the QUESTION - Does the abrupt change in positive angle of attack use more energy rather than just holding altitude and allowing the excess airspeed to decrease. Excluding the turn back situation as an added variable, any thoughts?
Doing a pull up like that is a waste of energy. Better to use the excess speed to turn towards a filed and get yourself setup and trimmed.
@@FlyWirescottperdue That does make sense but if Im cruising at 115 indicated and best glide is at 85 thats 25 knots of energy to swap for altitude. My dbout in this is the induced drag from the higher angle of attack. Of course I trust your aviation expertise ultimatly as it far exceeds my 800 or so hours. Great conversations though. Appreciate you as a professional. You really have effected pilots in a great way. Ty
V speed considerations are high altitude orientation where altitude is time. Low altitude orientation is airspeed is life and use airspeed to maneuver to the very near landing zone. You have six seconds. It will be obvious.@@PilotCooking
All good stuff relevant to a complex multi-factor situation, so thanks. One question I have in the Vy versus Vcc debate is about how much extra energy it takes to get back to the runway if climbing at Vcc, which puts the runway farther behind the airplane for any given altitude or any given time since liftoff, and therefore is the extra kinetic energy at failure if using Vcc worth it if it takes more than that extra energy to fly the extra distance back? FYI, I'm generally in the Vcc school of thought primarily because of the startle factor when the engine fails.
Good question. In a high wingloaded airplane you'll be pretty far from the runway before hitting your decision point of, for the F33C, of 1100-1300 ft. You will have plenty of energy to land on your selected spot, even if it isn't a runway. Don't be committed to the runway, commit to walking away.
This has worked for me in Pawnees and light Cessnas. From very low, what is available and survivable is immediately obvious in the first second, leaving five more seconds to maneuver. Only what we can see immediately in the very near hemisphere (Scott's ahead of the wing) is available. Having only two high altitude engine failures, I am not sure if startle factor leads to stall before working the emergency. Down low, aviate is all we have time for and the airplane will fly through the startle without stalling given cruise airspeed. Cruise is actually a bit too much. I also use/teach the energy management turn (law of the roller coaster) which involve wings level pull up to slow and reduce radius of turn. Next bank at whatever bank angle necessary at 1 g by releasing back pressure on the yoke as soon as bank is initiated.@@FlyWirescottperdue
This is really interesting. My homebuilt has a very low energy state at Vy. I have been climbing this way since I built it. What you are saying makes perfect sense. If I have to do a turn back it's probably not going to work out for me. Going to practice this at altitude. Thx for the info!
You have to pick up a section of a road to simulate a runway. We used only 1,000 agl to start the climb to 1,700 agl, power down, nose down, wing down to 45 bank. 270 Turnback.
With a fixed-pitch propeller Vcc climmbs are the way to go after clearing obstacles. The engine produces more power at the higher RPM it achieves at Vcc (versus Vy), which translates to rate-of-climb numbers that easily exceed climbs at Vy once you're 1000 AGL or better (but YMMV). Thanks for the total energy samples over time; very helpful info.
Energy of the airplane is irrelevant if the objective is to return to the departure airport. What matters is the ratio of the airplane’s energy to the energy required to return to the airport. If you increase the airplane’s energy by 10%, but it doing so put the airplane in a position where it requires 20% more energy to return to the runway, you haven’t won. I say the metric that matters is a ratio: Energy available/Energy required.
looks like someone got lost on the way to math class
@@BlastinRope How so? I am a retired engineer with a masters degree and licensed in multiple states. I haven’t added it up, but I probably have at least 40 credit hours of mathematics so please be very specific in your reply. Feel free to include equations if you feel the need.
@@LTVoyager oops I think I replied to the wrong comment
@@BlastinRope Bummer! You ruined my whole evening. I love to see people challenge me on math, or engineering, or science. It is always entertaining. 😂
Your energy state approach sounds like a great idea to me. However I didn't see the energy or energy ratios in the video. I did see "energy loss" in the vid with units of FPM which isn't really energy or even your E'=energy/m which should have units of FPM^2. I think it would be very instructive to look at total energy state (KE+PE) at a particular time after rotation (or simulated rotation at altitude), say 45 seconds and 1.5 min at the three climb speeds Vx, Vy, and Vcc immediately after rotation. Then you could look at the energy state after a 180 deg turn and compare. I would argue that it's not the energy loss from the beginning of the turn back (power loss) that is most important, but the total energy at the completion of the 180 deg turn that is most important, with the second most important being the energy state at the point of power loss. If you didn't want to use standard units of energy in joules to keep is simple for most pilots you could just define the normalized energy using a Vy climb as equal to 1, and calculate the others in relation to Vy. I actually seem to recall you talking about normalized energy but I never saw it in the video. Yes the results would be aircraft, bank angle/technique dependent but I think a very good data point would be your technique and aircraft. Keep up the good work - love your videos and your systems approach to flying!
Watch the first video in this series- 'The Impossible Turn- Is it Simplee? Is it Safe?'
@@FlyWirescottperdue Oh I'm sorry, I did watch that video and replied to this one for some reason... I think that this video is closer to what I was describing. It looks like you are using a PE' delta here though. I'm thinking a absolute total E' at the simulated power failure and the 180 would be instructive relative to each of the three climb speeds.
Is total energy at Vcc higher than Vy? Yes. You're missing the point of energy rate (power). If you're goal is to have the highest rate of energy at an engine failure, then yes, get as fast as possible. If you're looking to minimize your integrated low energy state risk, I will stridently disagree with you and state that climbing at Vy puts you out of the low energy risk state the fastest. You're also not addressing that you cover more ground at Vcc and this exceeds your Vg distance.
min sink best glide ?
Min Sink is less than Best Glide. It maximizes time airborne over distance given a certain altitude.
I understand what you're saying but my instinct is that flying at Vcc is a bit of cruch for poor training and bad preparedness to act to push the nose down if you lose your engine. I agree about Vx being way too close to stall speed for it to allow for enough reaction time but Vy should be enough. And since the total energy state is the sum of K and P energy it doesn't matter if you're lower and faster or higher and slower, you have the same energy. So really it's a choice between the two but one thing you didn't mention is the distance from the field. With Vy you will be closer at the same time vs at Vcc because your vertical speed will be higher and so the gradient will be too. And so it's not just a choice between being higher and slower and lower and faster but also higher slower and closer vs lower faster and further away. I will keep my climb outs at Vy personally because I train for engine out in the climb (I think at least it trains me for that) when I do hops on our 12k ft runway(t&gs with a climb to 150ft and then cut power and t&gs again and again..) and I prefer to be higher and closer, even if slower, than lower and further away, even if faster. I think being higher and closer to the runway is a better place to be. But I appreciate this series a lot, thank you for making it!
I did actually mention distance. I said that neither Vy or Vcc would get you back to the field in this airplane.
@@FlyWirescottperdue Oh ok, sorry I forgot about that. However I wonder if that is accurate, that neither would take you back. Have you tried, at altitude a 50° bank turn back? I am sure a shallow turn will not get you back but did you try a steep turn without pulling back. I don't know how much alt you would use but the turn radius would be tighter and the turn completed quicker, maybe quick enough. Just curious if you ever tested that?
@@markor2476 Mark, watch the Turnback videos I did with my A36 in particular. There is some good stuff in that Playlist I have in the description.
@@FlyWirescottperdue Will do
Practice makes perfect practice, iterations. Add in the startle time at Vy pitch attitude to see how safe that is. Inadvertent stall down low is fatal. We only get one. The three second estimate is an estimate. We don't have accurate simulators like the airlines do. Yes, any bank angle is available at 1 g if we do not load the wing by trying to not go down as steeply as the airplane with dynamic neutral stability wants (needs) to go down. Good technique to find something right here and not far away. Just don't pull back on the yoke.@@markor2476
To me, it always seemed being able to see over the nose was underrated.
Those radials are pretty opaque.
👍👍👍😎🇺🇸
This is terrific. Even better would be AOA targets. Small differences , but more precise. GA in general functions in airspeed. Great lead Scott thanks.
Hey Scott if you’re looking for content..consider a episode on oxygen, medical facts, regulations, reality , cost, maybe good?.
@FlyWirescottperdue - Scott, good video, and good discussion. I think for every takeoff we should have a plan. If you are in the middle of Kansas, it's very simple. Urban airport, the plan might be a bit more difficult. I think your suggestion of climbing over the airport to get to a safe altitude before leaving the safety cone of the airport should be done more commonly.
One area of future discussion might be use of flaps both on takeoff, and when to drop them if the engine quits. I almost never use flaps on takeoff (RV-8) but have thought about using 1/2 flaps just so that they are down in case of an emergency landing. Not sure my lizard brain will remember to get them down if my engine quits at 200 ft just after takeoff.
ATTENTION ICARUS's, fuzzy dice, air-sock and centrifugal force on chained objects equals a fail-safe attitude indicator. Figure it out. 🕛👁️👽⚡
You need to watch my 'Where's the Rock?' video.