New ingestion issue found with V-22s

If hybrid planocopters were viable they would have combined the two long ago.

The idea goes back to the 30,s with developments in the late forties upwards.

From what I'm heading there is not an inlet separator on the current engines. That allowed sand to enter the engine, causing a power loss.

a reply to: Zaphod58
Well thars ya problem...

a reply to: intrptr

So is my dad. He was an aerodynamic engineer at Lockheed.Ttook me to every airshow, and every time the Osprey demonstrated, he would explain it was a failure conceptually because, its not a plane or a helicopter, its both. And both does neither well.

If he was an aerodynamics engineer then from his perspective he probably wasn't and isn't wrong. I don't think that in itself means the Osprey is a bad aircraft. It isn't as good of a plane/helicopter as an actual plane/helicopter, however it does combine certain advantages of both (range/speed for example). The Harrier is another example. By most standards it's massively inferior to other CTOL fighters, however it allows it to fly from LHD's, giving a unique capability and allows fast jets to fly from smaller ships. The F-35B is also an example of this occurring.

I'm a Systems Engineer (usually electrical/electronics/communications side of things), I do not work in defence, but the methodology and processes are often the same. So my perspective is really a bit different. The real questions to me are:
- What did the USMC require from the Osprey program?
- Why was the Osprey concept chosen?
- Does it meet requirements?
- If the Osprey concept is flawed, then why did the USMC stick with it for so long?
- What is being done to solve the Ospreys problems?

So when the article you linked states that the aircraft sucks, the first thing i ask is:
Yes, but it that a customer requirement? Is that how USMC plans on operating the Osprey? Is that how the USMC operates its ships?

For example:

Fuel contamination is not an uncommon problem for the Navy and Marines, as many Navy ships store both fuel and water in the same tanks, which are then prone to build up certain kinds of fungi.
The resulting fuel contamination can cause dual engine flame-outs. And if an Osprey is operating at the same altitudes a helicopter does—around 500 feet—there’s little chance of gliding to a safe landing.

It seems daft for the USMC to operate this way if it is indeed a concern. iirc, the USMC also flies many single aircraft as well, including the F-35B. If fuel contamination is a concern then aircraft are usually not flown at all.

And if this is indeed a concern, I'm betting that if the V-22 is to be operated off a ship, then that ship will implement special processes to reduce the risk of fuel contamination. Do people really think that if there's a safety problem, engineers and operators just leave it, without mitigating the risk?

A CH-46 cost $6 million in 1987. That’s around $11 million in today’s dollars.

This assumes that the only thing that would increase the cost of the CH-46 between now and 1987 is inflation. This is not true at all.

Wikipedia lists the cost of an F-15E in 1998 at about 31 million dollars. Today the cost of a new F-15 (i.e. F15K) at over 100 million dollars. Yet 31 million dollars in 1998 dollars is only 45 million dollars today. So there are other factors that have escalated the cost of aircraft at a greater rate than inflation.

The CH-47 costs ~$40 million today, AH-1Z ~$31 million, and CH-53K $90 million (more expensive than the V-22 which costs ~$75 million). I would estimate the V-22 is probably around twice as expensive as a new build CH-46 with all the new bells and whistles, not 10x more expensive like the article suggests.

Is it worth it? Depends if the CH-46 could have met customer requirements...

originally posted by: Zaphod58
a reply to: MystikMushroom

Amazing isn't it. You read about how great these systems are now, but they were new and had the same problems we're seeing with the new equipment that's in testing, or still fairly early in operational stages.

The benefit is that in 30 years the F-35 will be amazing and the new "crap" should be scrapped.

Avweek has an open article now.

aviationweek.com...

The aircraft was in a hover and suffered a surge followed by power loss leading to a rolling forward landing that ended with a nose gear collapse and fire when they hit an irrigation ditch.

A second aircraft with them had a near miss after suffering a brief power loss. The likely cause was exceeding the Natops limit on RVL conditions. This was the aircrafts second time entering RVL conditions, and they remained in them for 110 seconds, Natops limits the time to 60 seconds.

The left engine ingested sand containing magnesium, calcium, aluminum, and silicon that then melted in the heat of the engine, and solidified on the fixed first stage turbine blade.

a reply to: C0bzz

Where did you get your information on water and jet fuel being stored in the same tanks? I've spent a lot of time on aircraft carriers and have never heard of that. I have heard of the fresh water tanks becoming contaminated with jet fuel, but, they are not stored in the same tank. We also pulled fuel samples before fueling our aircraft every time both on ship and ashore. Water is easily recognizable in jet fuel and the airframe and engine fuel filters would take care of any fungi that would be large enough to choke the engine's fuel supply.

a reply to: JIMC5499

My post was a response to what intrptr posted earlier in the thread.