Does R22 h-v diagram apply to approach

[Pohi]

My goodness.

 

On the chart posted that would be one heck of a steep approach to be in the h/v diagram. Try looking at a r22 chart and try to say that at no time the pilot is in the shaded portions.

 

The concept of developing a worse case scenario and if avoiding that, still being safe for other, less risky points, is lost by some.

 

I may be on the fence though, perhaps if somebody states how the chart is designed again, but uses capslock it will convince me that a h/v diagram is only for takeoff. Especially since a helicopter has no combination of airspeed and height above the ground during an approach.

 

[Mikemv]

Pohi, I never said "only for Take off" that was someone else? Also, notice on the chart where the developers of the HV diagram placed the recommended approach profile!

 

Your considerations about making safe approaches are all good but the HV diagram does not give you information about them.

 

Best wishes, (without capslock)

 

Mike

[Pohi]

Its sad, and I hate to even admit it, but I just read 3 articles about development of the H/V diagram. 1 written by NASA, and the other two published by the FAA when they developed the curve.

 

They never mentioned approaches. Of course, on the same hand they never talked about take off either. They just talked about low hover, high hover, and setting different airspeeds and altitudes.

 

They even showed a diagram of how the test was set up. The engine failure was initiated basically on the final leg once the pilot established the proper airspeed and altitude. I couldn't find anywhere where they talked about setting up a max power climb, or any climb for that matter. It was all in straight and level flight.

 

By reading that, since it says nothing about either takeoff or landing, then the diagram must therefore apply to neither. It must be for straight and level cruise flight, or hovering.

[rodrop]

The H/V example provided in a recent article/column in AOPA has a title/comment on it that states

"Avoid operation in shaded area". I am not near a POH, but I will check when I get home to see if my POH has the same comment/title.

Again, I am not an expert, and if you read my first post, you now will notice I am swaying to the side that says it is not just for take offs.

 

??

[gary-mike]

The H/V example provided in a recent article/column in AOPA has a title/comment on it that states

"Avoid operation in shaded area". I am not near a POH, but I will check when I get home to see if my POH has the same comment/title.

??

 

Mine does. (for R22)

 

It says

DEMONSTRATED CONDITIONS:

SMOOTH HARD SURFACE

WIND CALM

103-104%RPM

 

And right above the chart

AVOID OPERATION IN SHADED AREAS

 

Without any training, I thought the chart was pretty simple (it says avoid operation in the shaded areas). It make sense to me, don't fly like your but is on fire 5' off the deck, and don't try to hover fully loaded OGE. How far off am I? I love these threads that I can learn from, opposed to the bickering back and forth about someones business model, or lack of drive to get a job.

 

My question about the HV chart is, how do you get confined are landings to fit into the HV curve? For example if I were to fly an R22 the HV curve puts me at under 10' AGL until I am at 50 KIAS (7000' DA at 1,300lb). That doesn't seem like it would be a very confined area.

 

edit: Once in a confined area, how do you take off within the HV curve?

Edited December 20, 2011 by gary-mike

[C of G]

My question about the HV chart is, how do you get confined are landings to fit into the HV curve? For example if I were to fly an R22 the HV curve puts me at under 10' AGL until I am at 50 KIAS (7000' DA at 1,300lb). That doesn't seem like it would be a very confined area.

 

You don't. Is the confined area a smooth, hard surface?

 

Sometimes you are sticking your neck out. You want to keep your risk exposure to a minimum, but there is always a risk.

[aeroscout]

I think if you hit the last third of your approach with 40 knots at 40 feet, and decrease each by one to touchdown, it would not only be doable, but well within HV.

[gary-mike]

I think if you hit the last third of your approach with 40 knots at 40 feet, and decrease each by one to touchdown, it would not only be doable, but well within HV.

 

I just noticed my critical grammatical error. I asked the question of how to get a confined area landing into the HV curve. What I should have said is confined area take off. Obviously completely opposite... Long day in the cubicle, but hey I knew what I was thinking.

Now I must go edit my question and head to the car to grab my RFM.

 

Thanks for the free schooling.

[Spike]

FAA-H-8083-21

 

“A height/velocity (H/V) diagram, published by the manufacturer for each model of helicopter, depicts the critical combination of airspeed and altitude should an engine failure occur. Operating at the altitudes and airspeeds shown within the crosshatched or shaded areas of the H/V diagram may not allow enough time for the critical transition from powered flight to autorotation. “

 

No mention of what you are doing (climbing, descending, hovering, inverted…..) while operating at the altitude or airspeed within the shaded area. Simply being in the shade is enough…..

 

It’s to my understanding; the edges of the shaded area are the points where the test pilots called it quits during the flight test certification process. Therefore, the shaded areas are simply unknowns hence the term “may” in, may not allow enough time….. If the sentence read “will”, as in “will not allow enough time”, it would more-than-likely be a limitation…. IMHO of course…

[alexc]

Looks like one diagram for all is kind of muddy. FAA should require manufacturers adding another dimension to H/V diagram: high power setting H/V diagram, low power setting h/V diagram (I created a demo below). Other power settings and conditions can be interpolated. Other factors, such as, pilot skills, landing conditions, wind, etc are too fine grain for heli engineers.

 

High power setting is for takeoff, cruise, OGE hover, etc reference. Lower power setting is for normal approach, descend reference.

 

 

 

Look this guy doing 0-Speed Autorotation from 100-200 feet, pretty crazy:

[alexc]

try again to post the picture.

[C of G]

try again to post the picture.

 

What you've provided is exactly the point. The H/V diagram is set only as a certification criteria. Anything else is purely a guess. So, to that end, it doesn't apply as published in written form to anything other than the conditions under which it was demonstrated and extrapolated.

 

The same as any other chart you see in the performance section. In my opinion, the FAA certainly does not need to publish any other charts based on power settings or any other variable (RRPM, Gross Weight; Technique; Etc.) There are just too many. You will occasionally see different charts in the same manual when it is to the manufacturer's benefit. Pilots should simply understand the certification criteria and use their best judgement as to how they apply to how/where they are flying.

 

Take the hover controllability demonstration as an example: It is simply a reference used for certification. It doesn't mean you will lose control at 18kts, same as the h/v curve doesn't mean you will ball it up on one side or the other. Understand how it was developed and use your best judgement in application.

Edited December 21, 2011 by C of G

[aeroscout]

Excellent conversation, I don't care who you are.

[iChris]

Its sad, and I hate to even admit it, but I just read 3 articles about development of the H/V diagram. 1 written by NASA, and the other two published by the FAA when they developed the curve.

 

They never mentioned approaches. Of course, on the same hand they never talked about take off either.

 

I couldn't find anywhere where they talked about setting up a max power climb, or any climb for that matter. It was all in straight and level flight.

 

By reading that, since it says nothing about either takeoff or landing, then the diagram must therefore apply to neither. It must be for straight and level cruise flight, or hovering.

 

 

You need to go back to the well for more water. Read AC 27-1B, pages B-37 thru B-45 for a more detailed explanation.

 

This AC (Master AC 27-1B thru Chg 3) establishes an acceptable means of compliance with Part 27: CERTIFICATION OF NORMAL CATEGORY ROTORCRAFT

 

Don’t over complicate this subject. There is no regulatory language making the height-speed envelope a limitation for any single engine helicopter. CFR 27.87 calls for a height-speed envelope and related information be included in the performance section of the RFM, warning the pilot of a potential hazard following an engine failure at low altitude/low airspeed.

 

The following is an example of the Informational nature of this data from the Bell 206 RFM (Section 4):

 

“The Bell 206B Jet Ranger III performance data are contained in this section. The data listed on the graphs are derived from actual flight tests and are intended to provide information to be used in conducting flight operations. The performance data contained herein is applicable to the 250-C20B/C20J engine.”

 

CFR 27.87 Height-speed envelope: (a) If there is any combination of height and forward speed (including hover) under which a safe landing cannot be made under the applicable power failure condition in paragraph b.) of this section, a limiting height-speed envelope must be established (including all pertinent information) for that condition, throughout the ranges of—

Edited December 21, 2011 by iChris

[Pohi]

lets try this. Simple as it gets

 

http://www.casa.gov.au/wcmswr/_assets/main/fcl/exams/cyberexam/bell206l1_extract.pdf

 

Bell 206 RFM, page 20 and 21.

 

"Avoid operations in shaded areas"

 

If, hovering, flying, landing, and take offs are all "operations", then they should be ______?

 

A. Encouraged

B. Avoided

C. Avoided, except for landing

D. None of the Above

 

This is part of your grade folks, and will be on the final exam.

 

Lets not let preconceived notions get in the way of 3rd grade reading comprehension.

Edited December 21, 2011 by Pohi

[Mikemv]

"Operations" to which the HV diagram is derived from!!!!!!

 

Not anything "you" want to label as an operation to try to validate your ideas.

 

Take an aerodynamics class on the transitions from powered flight to autorotative flight and clear this up for yourself.

 

Did I mention that Nick Lappos validates what we are saying in the HAI FIRC?

 

Have you read any of Prouty's books?

 

Best Wishes,

 

Happy Holidays to All

 

Mike

[Pohi]

"Operations" to which the HV diagram is derived from!!!!!!

 

Not anything "you" want to label as an operation to try to validate your ideas.

 

Take an aerodynamics class on the transitions from powered flight to autorotative flight and clear this up for yourself.

 

Did I mention that Nick Lappos validates what we are saying in the HAI FIRC?

 

Have you read any of Prouty's books?

 

Best Wishes,

 

Happy Holidays to All

 

Mike

 

Nick Lappos and I are tight. He told me last night over a few drinks that he just tells you that he validates what you say to make you happy. I was hoping to not have to mention that on a public forum.

 

I not only read Prouty's books, but I was an editor on the last one.

 

And, I don't need to take an aerodynamics class to clear up reading comprehension.

 

Now can we continue, since that is all out of the way?

 

I just double checked all the available POH, RFM, -10 I have access to. They must not be updated because they do not say "Avoid operations (to which the HV was derived) in the shaded areas." I guess I must not have the updates.

 

So we can be all on the same page,

 

http://ecfr.gpoacces...1.0.1.1&idno=14

 

Since it is the FAA we are talking about, why don't we use their definition? Since they wrote the books.

 

Operate, with respect to aircraft, means use, cause to use or authorize to use aircraft, for the purpose (except as provided in §91.13 of this chapter) of air navigation including the piloting of aircraft, with or without the right of legal control (as owner, lessee, or otherwise)

 

and, just so we cover all our bases,

 

§ 91.13 Careless or reckless operation.

 

(a) Aircraft operations for the purpose of air navigation. No person may operate an aircraft in a careless or reckless manner so as to endanger the life or property of another.

( Aircraft operations other than for the purpose of air navigation. No person may operate an aircraft, other than for the purpose of air navigation, on any part of the surface of an airport used by aircraft for air commerce (including areas used by those aircraft for receiving or discharging persons or cargo), in a careless or reckless manner so as to endanger the life or property of another.

 

So, I guess unless you consider approaches to landing careless or reckless (I've never flown with you, so I have no opinion on the matter. Who knows, perhaps the H/V diagram does not apply to you), then they count as an operation.

 

And, as a wise man said....

 

Not anything "you" want to label as an operation to try to validate your ideas.

 

As a side note, I really don't care how electricity is made. It's irrelevant. I don't care how a toaster is made. It is also irrelevant. But when the directions on the box say not to make toast in the shower, I go ahead and follow the directions.

Edited December 21, 2011 by Pohi

[C of G]

I sincerely appreciate your sarcasm.

Edited December 21, 2011 by C of G

[aeroscout]

Quote from page 2 poster,

 

If, hovering, flying, landing, and take offs are all "operations", then they should be ______?

 

Answer;

 

Conducted.

 

All 3 can easily be accomplished outside of the shaded area, and well within the successful autorotative capabilities of the rotorcraft. Remember, autogyros do all three, and are in a permanent state of autorotation.

[Pohi]

Quote from page 2 poster,

 

If, hovering, flying, landing, and take offs are all "operations", then they should be ______?

 

Answer;

 

Conducted.

 

All 3 can easily be accomplished outside of the shaded area, and well within the successful autorotative capabilities of the rotorcraft. Remember, autogyros do all three, and are in a permanent state of autorotation.

 

I like where your head is at, but we are talking in regards to a h/v diagram and it's shaded area. I did not think it necessary to include that verbiage in the question.

 

If we were to avoid all operations such as takeoff, cruise, and landing we would be truck or taxi drivers.

[Pohi]

I sincerely appreciate your sarcasm.

 

:-)

 

I'm glad there is still a sense of humor here in the forums.

[R22139RJ]

Pohi, I'm glad you have the bravery to post your lack of comprehension on the forums. Again, bringing to the surface more shortcomings in the training of commercial pilots.

 

I suggest taking a seminar.

[Pohi]

Pohi, I'm glad you have the bravery to post your lack of comprehension on the forums. Again, bringing to the surface more shortcomings in the training of commercial pilots.

 

I suggest taking a seminar.

 

Haha, wilco

[Shaun]

I did a checkride with a DPE who insisted the HV diagram was for landing, thus the approaches he wanted to see were fast and low with a rapid decel at the end. That maneuver has far more risk, even if it theoretically might give you more energy for an autorotation.

[Pohi]

Using the reccomended takeoff profile backwords for approach to landing is kind of a silly idea. I have heard that before though, must have been interesting.