[S-92] Autorotation Video
Graviman,
At the risk of taking the thread somewhat off-topic, if you had electronic drive for tailrotors, would you control tail rotor thrust by varying RPM or pitch or (probably) a combination?
At the risk of taking the thread somewhat off-topic, if you had electronic drive for tailrotors, would you control tail rotor thrust by varying RPM or pitch or (probably) a combination?
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I think you are right, Nick.
This thread is in a death spiral.
Let's talk about real flying.
Dual engine failure calls for the following procedures:
1. Full left pedal
2. Monitor the OAT gauge
3. Recalling the reported surface temp durng flight planning, pull all the pitch you have when the OAT is 2C above forcasted. This is of course to account for the lag in the OAT gauge.
This King Bee Lead. I go now!
This thread is in a death spiral.
Let's talk about real flying.
Dual engine failure calls for the following procedures:
1. Full left pedal
2. Monitor the OAT gauge
3. Recalling the reported surface temp durng flight planning, pull all the pitch you have when the OAT is 2C above forcasted. This is of course to account for the lag in the OAT gauge.
This King Bee Lead. I go now!
S-92 Autorotation Video
Dear Thomas:
Not sure I understand what "shoddy" means.
Over the years at Sikorsky, I made the first power off touchdown autorotations in the UH-60, the SH-60, the S-76A and the S-92. Along the way, I had to teach the US Army team doing the evaluation of the S-67 Blackhawk how to do autorotations to the ground as a part of their evaluation. That hadn't been done before either.
Point is they all look pretty much alike; no dents, no dings, and all landing gear and structural loads well within limits.
Best of all, the meat wagon went back to its parking place empty.
If that is shoddy, its for me!
John Dixson
Not sure I understand what "shoddy" means.
Over the years at Sikorsky, I made the first power off touchdown autorotations in the UH-60, the SH-60, the S-76A and the S-92. Along the way, I had to teach the US Army team doing the evaluation of the S-67 Blackhawk how to do autorotations to the ground as a part of their evaluation. That hadn't been done before either.
Point is they all look pretty much alike; no dents, no dings, and all landing gear and structural loads well within limits.
Best of all, the meat wagon went back to its parking place empty.
If that is shoddy, its for me!
John Dixson
S-92 Autorotation Video
Dear Lutefisk989,
Your note is absolutely correct, but during development/certification testing, the simulation tools are simply lagging the whole process and nowhere near in the state to convince anyone as to their validity in assuring that a replication of the entire autorotative landing would be valid. In fact, at certification we were still using flight test data to update/upgrade/modify the Flight Safety S-92 simulation, not the other way around.
So in reality there was not much choice: the landing had to be done.
Thanks,
John
Your note is absolutely correct, but during development/certification testing, the simulation tools are simply lagging the whole process and nowhere near in the state to convince anyone as to their validity in assuring that a replication of the entire autorotative landing would be valid. In fact, at certification we were still using flight test data to update/upgrade/modify the Flight Safety S-92 simulation, not the other way around.
So in reality there was not much choice: the landing had to be done.
Thanks,
John
Hovering AND talking
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Not sure I understand what "shoddy" means.
i.e. inferior.Cheers
Whirls
I did not communicate my intent very well in my last post. As Nick indicated, the regs to not require a "no-ground run" EOL. The ACs recommend a touchdown speed of <40 KTAS. I have had the privilege to be involved with these types of tests (FTE), and the slide can go on for many seconds/feet. Result? Skid shoes and skids: Worn out. Test: Passed. Steak dinner and beverages afterward: Well-deserved.
ET Pilots ARE Gods.
PT Pilots just THINK they are!!
E = Experimental
P = Production
PT Pilots just THINK they are!!
E = Experimental
P = Production
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Originally Posted by John Dixon
Point is they all look pretty much alike; no dents, no dings, and all landing gear and structural loads well within limits.
RobboJock, the most successful engineering developments are ones which come of their time. I suspect TR e-drive would initially sit as a back up to a mechanical system. This might later evolve into the ability to break the mechanical link and reduce Ntr in case of hub problems. Later confidence might grow high enough to use two e-drive systems in place of the mechanical system. Then Ntr could be performance optimised.
Last edited by Graviman; 22nd Aug 2007 at 17:42.
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An interesting discussion because it mixes the two concepts of Certification and Operation (as may the S92 RFM); consider this, when an S92 is cruising at 10,000ft with 19 passengers and large amounts of fuel such that it cannot meet a 50ft/min ROC, under what conditions is it operating.
When it comes to Cat-A, I think the folks who really "get it" operationally are the Europeans, because they must operate under "Performance Class" concept.
In this regard, I like how the JARs have effectively associated Cat-A with certification, and PC-1/2/3 with Ops (kind of like the difference between VFR and VMC, or IFR and IMC). Since the FAA hasn't adopted the Performance Class concept, Americans tend to forget that operating under Cat-A means three things: (1) you're within WAT limits; (2) you're using the published t/o and landing procedure; and (3) you can meet published obstacle clearance.
Oh, and to answer your question about 10,000': i dont' think it's operating under any conditions, with respect to Cat-A. When you parse the take-off and landing requirements for Cat-A, you'll see that it ends/begins at 1000' above the surface. Boy has performance planning become complicated, when you mix Cat-A/B with IFR!
JohnD: I'll say it again ... nice autos!
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Zebedee,
To the water. Did about 200 to 250 over a three-year period before we got rid of them. Used to take a B206 on fixed floats and do autos with all company pilots, once a year. All to touch downs on the water.
To the water. Did about 200 to 250 over a three-year period before we got rid of them. Used to take a B206 on fixed floats and do autos with all company pilots, once a year. All to touch downs on the water.
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Bushfire,
It is a safe bet that every helo you have ever seen has been tested in auto to the ground. The 53 autos were done by a great TP at Sikorsky, Jack Peterson, who was a Corsair pilot during WWII. We kidded him that anyone who did a full auto in an H-53 needed a 53 to carry his gonads.
It is a safe bet that every helo you have ever seen has been tested in auto to the ground. The 53 autos were done by a great TP at Sikorsky, Jack Peterson, who was a Corsair pilot during WWII. We kidded him that anyone who did a full auto in an H-53 needed a 53 to carry his gonads.
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Hey Tailspin, Just a simple question. When you go down, does yer OAT’s go up or down????
As far as first on types go, my vote goes to Uncle Frank's’ lightweight blade first model. Tim tucker wasn’t it? No simulators or computer modelling there, Uncle Frank never owned a computer until recently they reckon, Just a slide rule and the back of a second hand envelope.
Somewhere recently someone was talking about exceedances, and then I saw a comment about power recovery in a S92.
Struth.
That reminded me of a cartoon that I vividly remember from my pre teens years. It featured Yogi Bear who had gotten mixed up in a knuckle-up with a real - big - bad - bear. Yogi got a smack in the mouth and the next picture showed Yogi with a real dumb surprised look on his dial, spitting out a stream of molars. Very funny I thought.
I could see the S92 driver just the same, dumb surprised look on dial, all the gears and turbine blades in a stream out the back, going west.
As far as first on types go, my vote goes to Uncle Frank's’ lightweight blade first model. Tim tucker wasn’t it? No simulators or computer modelling there, Uncle Frank never owned a computer until recently they reckon, Just a slide rule and the back of a second hand envelope.
Somewhere recently someone was talking about exceedances, and then I saw a comment about power recovery in a S92.
Struth.
That reminded me of a cartoon that I vividly remember from my pre teens years. It featured Yogi Bear who had gotten mixed up in a knuckle-up with a real - big - bad - bear. Yogi got a smack in the mouth and the next picture showed Yogi with a real dumb surprised look on his dial, spitting out a stream of molars. Very funny I thought.
I could see the S92 driver just the same, dumb surprised look on dial, all the gears and turbine blades in a stream out the back, going west.
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Lutefisk989 -
I would have to think hard about what is safer and even able to prove. If you accomplish an auto to a point in space, in a max gross weight machine, and are trying to prove ZERO rate of descent and acceptable forward speed, you will need to have DGPS, cameras filming the point in space ect.. When you perform the maneuver you will be flying that max gross weight machine to a point in space, performing a good flare, getting the forward speed (hmmm are we referencing ground speed with no wind via a GPS or relying on an airspeed indicator during a large flare) to an acceptable speed- then we will push forward cyclic to get the nose down to at least level if not an accelerative attitude, which will further decay NR. Now we will be getting the PLA back to the fly position, NR will be below normal and we will be re-entering autorotation while the engines are coming up to catch the NR. I think I like touchdown autos, and in the heavy ship I will take the groundslide/roll, at least I have normal pilot references to the ground, and am proving confidance in the machine design. You will also be accomplishing work-ups from faster touchdown to slower as you gain experience and probably will start at a lower gross weight at first as well as doing a few power recoveries in the flare during work-up.
I would have to think hard about what is safer and even able to prove. If you accomplish an auto to a point in space, in a max gross weight machine, and are trying to prove ZERO rate of descent and acceptable forward speed, you will need to have DGPS, cameras filming the point in space ect.. When you perform the maneuver you will be flying that max gross weight machine to a point in space, performing a good flare, getting the forward speed (hmmm are we referencing ground speed with no wind via a GPS or relying on an airspeed indicator during a large flare) to an acceptable speed- then we will push forward cyclic to get the nose down to at least level if not an accelerative attitude, which will further decay NR. Now we will be getting the PLA back to the fly position, NR will be below normal and we will be re-entering autorotation while the engines are coming up to catch the NR. I think I like touchdown autos, and in the heavy ship I will take the groundslide/roll, at least I have normal pilot references to the ground, and am proving confidance in the machine design. You will also be accomplishing work-ups from faster touchdown to slower as you gain experience and probably will start at a lower gross weight at first as well as doing a few power recoveries in the flare during work-up.
S092 Autorotation Video
Thanks for the comment, Lutefisk.
You know the FAA required that we perform a power off landing as part of the S-76A cold weather certification. So we were flying at the Inuvik, NWT aorport and I was lucky to be flying with Jim Kay, who did the S-64 development and flew with Frank Tefft doing the CH-53E development. The FAA pilot could have insisted on doing this one, but chose to let us do it.
Anyway, these things are one-time events, and past success doesn't count.
So we came around the pattern, put the gear down and proceeded to do a "shoddy" power-off landing. I thought it was OK as we rolled forward, and then looked over at jim Kay who was laughing. "Come on Jim, it wasn't that bad" is what I recall saying. " No, John, it was fine, but I didn't turn the on-board instrumentation on, so you'll have to do another one" was his response!
You know the FAA required that we perform a power off landing as part of the S-76A cold weather certification. So we were flying at the Inuvik, NWT aorport and I was lucky to be flying with Jim Kay, who did the S-64 development and flew with Frank Tefft doing the CH-53E development. The FAA pilot could have insisted on doing this one, but chose to let us do it.
Anyway, these things are one-time events, and past success doesn't count.
So we came around the pattern, put the gear down and proceeded to do a "shoddy" power-off landing. I thought it was OK as we rolled forward, and then looked over at jim Kay who was laughing. "Come on Jim, it wasn't that bad" is what I recall saying. " No, John, it was fine, but I didn't turn the on-board instrumentation on, so you'll have to do another one" was his response!
Last edited by JohnDixson; 23rd Aug 2007 at 15:59. Reason: Add S-76A wording