Comments on: Osprey Ready for Primetime? Part One

By: MrsDigger

MrsDigger — Thu, 04 Oct 2007 15:13:19 +0000

Of course CDI is against the program…although they portray themselves as a “non-partisan” group, they are a who’s who of liberal democrat fundraisers. They originated from the 1970’s Fund for Peace. CDI’s next target is the F-22 program. Keep an eye open; they have it in for ALL defense spending.

By: osprey crew chief

osprey crew chief — Wed, 05 Sep 2007 13:50:08 +0000

vortex ring state can be avoided in the osprey! just by rolling the nacelles down. what other helo can do that? i will admit i was scared to death to fly on the osprey at first. but after taking my time to learn the aircraft by working on it, not reading about it. i have come to love this airframe. the possibilities are endless and alot of lives are going to be saved because of this aircraft. just ask anyone who has worked on them. flying in the Marine Corps is 100% volentary so no one would fly on it if they did not feel safe!!!

By: Mairead

Mairead — Tue, 30 Jan 2007 10:04:43 +0000

“The surviving engine doesn’t “take over instantly”. The rotor drive trains are mechanically linked. Unless the drive train breaks, both rotors always stay at the same rpm.“
Really? What’s all this about then: “Under normal operating conditions, each proprotor gearbox is powered by the nearest engine via the engine output shaft. In the event of engine power loss, the proprotor gearbox associated with the failed engine receives power from the opposite engine through the interconnect drive system.” (http://www.globalsecurity.org/military/systems/aircraft/v-22-survive.htm) ?
I agree that the surviving engine won’t take over instantly–but that seems to be the hope.
You cheerleaders should see if you can’t qualify as aircrew on them. Then it’d be *your* lives on the line too. There’s nothing like risking your very own one-and-only personal butt to motivate a re-think about what’s ‘acceptable’.

By: chuck

chuck — Tue, 30 Jan 2007 03:22:36 +0000

“In an Osprey, Vortex Ring State causes it to roll and crash, as only one prop loses thrust.“
How is that different than a Phrog, which also has two rotors? The only difference is front/back versus left/right.
“Moreover, the Osprey’s surviving the loss of a single engine during STOL operation depends on the fragile technology of the surviving engine being able to take over *instantly* and drive both propellors strongly enough to prevent a fatal roll.“
The surviving engine doesn’t “take over instantly”. The rotor drive trains are mechanically linked. Unless the drive train breaks, both rotors always stay at the same rpm. This is similar to the system on a Phrog, which as noted above also has two rotors, with all the same issues surrounding maintaining power to both rotors. The fact that the Phrog’s rotors are front/back versus left/right provides absolutely no safety advantage (at least not in regards to powering the rotors). If the Phrog lost lift in one rotor, it would flip and crash. If the Osprey lost lift in one rotor, it would roll and crash.
“blackhawk’s climb/descent rate, I believe, is 2000 feet/minute“
That sounds at least 50% too high.

By: Nathan

Nathan — Mon, 29 Jan 2007 17:19:42 +0000

Will more soldiers die in Ospreys because the pilot descended too quickly despite additional equipment, software, and training? Yes but not in numbers significantly different than combat helicopter losses.
The osprey is a revolutionary aircraft. It offers the ability to self deploy, use aerial refueling, with longer range and reduced susceptibility en route to the fight at the price of additional vulnerability to ground fire when deploying troops compared to a dual engine heavy copter (IMO). As long as it’s used intelligently, it is well worth the trade off and should ultimately save lives.

By: Mairead

Mairead — Mon, 29 Jan 2007 15:20:57 +0000

Glide? You must be joking. My field isn’t aeronautics, but one look at that wingspan tells me it will glide like a rock.
The gliders used as assault transports in WW2 had only a 1:10 glide angle because of their limited wingspan, compared to 1:22 for standard gliders. But even their wingspan was on the order of 2X the Osprey’s, and their airframe was much closer to a traditional glider’s airframe: fabric-covered wood and light metal tubing stringer construction, no engines.
Moreover, the Osprey’s surviving the loss of a single engine during STOL operation depends on the fragile technology of the surviving engine being able to take over *instantly* and drive both propellors strongly enough to prevent a fatal roll.
Don’t kid yourself. That thing is nothing but a disaster with engines. If it goes into production, all the contractors and the uniformed program staff will be living off the blood of the Marines it kills.

By: tz

tz — Sun, 28 Jan 2007 19:26:58 +0000

The Osprey does both (windmill and glide) however. In a catastrophic failure of both engines (which there is a very slim possibility of happening) it can do either/both. Remember in a autorotation, it is not just a straight down descent!! In fact, that would destroy a helicopter quickly when it hit the ground. There is a forward component to it as well, something the Osprey is better suited to take advantage of because it has wings. The wings dont fall off that easily. Plus as previously mentioned, the Osprey can totally lose one engine and still keep on flying. Again, this is an advantage that most US helicopters do not share. Helicopters also have a very vulnerable tail rotor, unlike the Osprey. If that thing quits, you are in a world of trouble as well. It “guarantees a catastrophic failure”. Plus many US Helicopters are vulnerable to a phenomena known as mast-bumping, where literally the rotors do fall off the helicopter. The Osprey does not exhibit this phenomena due to the structure of its rotor hub. So, I do not see what is so catastrophic about failure in the Osprey. Please provide specifics next time, particularily as compared to similar helicopter/plane malfunctions.
Any way you put it, aviation is a dangerous game. Particularily in helicopters where the margin for error is small and the things that can go wrong are multitudinous. Our current generation of helicopters as well are ancient things that are reaching the end of their lives for the most part, and the Osprey represents a much safer alternative. I pay attention to the Class A mishap reports… do you?

By: Mairead

Mairead — Sun, 28 Jan 2007 14:34:06 +0000

Any engineer worth the name knows that failures are guaranteed. It’s the nature of the physical universe. So a big engineering task is always to change catastrophic failure into survivable failure.
The Osprey guarantees catastrophic failure by design. If it cannot windmill down, and it cannot glide down, then any time something happens to one of the propulsion subsystems, that aircraft and its occupants are dead.
The effect is the same as if, in a conventional aircraft/helicopter, engine failure were to result in a wing/rotors falling off. How many such aircraft would ever be accepted for duty?
This is not rocket science.

By: pedestrian

pedestrian — Fri, 26 Jan 2007 14:39:03 +0000

>There is already a ramp-mounted M-240 and they are (I think) reviving a 20mm chin gun similar to
>the Cobra’s. This was put on hold during development. I have talked to many of the current
>pilots and a large number of phrog guys who all are big fans, and have a ton of confidence in it.
I’ve heard that the plan to add weapons was uphold, but I never heard any news afterward. Thanks for the comment that it sound like it’s being reconsidered. There are also other considered alternatives and plans. These include V-22 tilt rotor escort, UAV, and directed energy weapon. The rotor on the side is just in a bad place to add weapons on the wings. I would love to see an AV-22 with some missiles (including stinger missile) and rocket pods added, something similar to the Russian Hind where you could provide close air support for the troops it dropped.

By: tz

tz — Fri, 26 Jan 2007 04:09:14 +0000

The deal about vortex ring state and the Osprey is not a big deal. The Osprey is just as, if not less susceptible to it as any other helicopter is. In fact, the only reason they really were having a problem with it in the first place, and one of the contributing factors to that Class A mishap where all those Marines were killed was that the Marine Corps was transitioning both fixed and rotorary winged pilots to the Osprey. Some of the fixed wing pilots were not as familiar with VRS as the helo guys were and therefore unsafe in the aircraft. This has since been remedied by extra training and safety aids. As they say, NATOPS is written in blood. Also, as for rotor down landing, this is possible in an ELP scenario to do safely. The rotors break away away from the body of the aircraft. Furthermore, it is handleable in single engine scenarios, unlike the Phrog (CH-46). Finally, the room inside it is larger than the CH-46 and they are working on getting it defensive weaponry. There is already a ramp-mounted M-240 and they are (I think) reviving a 20mm chin gun similar to the Cobra’s. This was put on hold during development. I have talked to many of the current pilots and a large number of phrog guys who all are big fans, and have a ton of confidence in it. Its range additionally gives us more training opportunities as you can get more Xs out per hop. I also have been on one several times, and have been impressed each time. That large crash and the time it has taken to develop have just given it a bad rap. Plus CDI is known to be a luddite almost anti-military think tank. The technology involved in it is so new, it is a wonder that it has gone so well!! Any new technology has growing pains. Look at the F-14, Blackhawk, M-2, F-18, etc. and you will see a difficult birth. Most of these are now tried and true members of the military, but went through developmental phases that involved sometimes several crashes. However, the F-18 and F-14 are single or dual seat aircraft, which were being flown by test pilots, so people hardly noticed. However, when you have a dual piloted aircraft with 1 or 2 crewchiefs/aircrew and 30 guys in the back, this creates much more of a stir! Hence the subsequent bashing of the Osprey.
PS– the speed isnt the capability the Marines are most excited about. While nice, and you are hard to hit, the big thing is the range and payload it gives. When you are flying almost always from a boat to your destination, it gives the Marine Corps much more of a reach to things like Embassys and other targets. The oft cited example used by my Osprey peers was the Iran hostage crisis. The entire mission could have been flown with room to spare and no dicey refueling in under one night with 6 hours of planning for the air side. Now tell me that isnt a useful capability!