Just out of curiosity, what engine are you using in the replica?
Tony,
Thanks for taking the time to check this. We had actually checked the Catalina beaching gear idea, but discounted it.
The wall thickness of the tire is very thin, so in my mind it might be possible that it would inflate to a shape like that of the Hudson photo posted earlier. Other than that, I´ve no idea
Air Ministry,
Thank you very much for this information!
For some stupid reason, I´d not thought about something like the Hudson!
Small amounts of water ingested into the intake, ie. snow, will aid an increase air density, and therefore INCREASE engine efficiency…
Snow occurs in cold air – which is better for the engine, ie. more dense, and will make the engine INCREASE efficiency…
Well you´re right! Water will increase engine performance up to a degree. Some turboprops (basically a jet engine turning a propeller) have water/methanol mixture injected into the engine to increase power. Off the top of my head, I can only think of the Garret TPE series and the RR Dart that used this method. Both are direct drive engines. Free wheeling turbines don´t seem to use this to increase power (the PT-6 does not) but I´m happy to be corrected! NO jet engine I know of has EVER used water/methanol spry during routine airline operations to increase power, but again, I´m always happy to learn something new.
While on the subject of water ingestion into jet engines, it can become too much at times. I know of one instance when flying through a monsoon rainshower with engines at idle, one engine flamed out at 15.000 feet due to rain.
With regards to cold, it is true. Engines perform better in cold environment, but for the purpose of the discussion it is hardly relevant.
Since I´ve busted the collective brains of the forum I need advice about how to proceed. Where do you think I can get some info about this tire?
Flying through snow has no effects on jet engines. The snow will melt in the heat inside the engine. However, snow/ice that builds up on the engine inlets can be a problem. It will disturb the airflow into the engine, and if it breaks off in big chunks can damage the engine, or cause flame out when it melts into lots of water.
That is why all jet engine inlets are heated by hot air taken from the compression section of the engine (bleed air). The bleed air is very hot (typically about 300°C or more) and is ducted to the front of the engine inlet. That is why, on most jet engines you´ll see a metal coloured stripe around the inlet. It is the heated portion of the inlet.
Taking bleed air from the compression section of the engine, will have effects on engine performance. During most of the flight, the engines are operating well below maximum power so when the engine anti ice is switched on the engine will automatically increase the power/fuel flow to compensate for the bleed air being drawn from it. The power increase is not apparent on any cockpit instrument except the fuel flow meter, and even on that instrument the change is so small as to be almost unnoticeable. For prolonged flight in iceing conditions a ball park figure for fuel flow increase is about 5% for most engines.
During take off, were engines are operating at maximum power, the small increase in power necessary to compensate for the engine anti – ice is not available. In that case, the loss of power is compensated for by reducing the maximum allowed take off weight. The amount of weight reduction is VERY variable and will depend on aircraft type, engine type, runway length and airport elevation just to name a few variables. I´ll not be drawn into discussing Flex/Assumed temp take offs, as that will be a can of worms at this stage! ;):D
Well, after Air Ministry´s excellent input, it looks like I can forget all about this being a Walrus tire!
As promised, I went to the hangar today to take some pictures.
This is how the offending tire looks like:
http://i32.photobucket.com/albums/d22/Galdri/006-1.jpg
The tire is approximately 3 inches wide
http://i32.photobucket.com/albums/d22/Galdri/009-3.jpg
http://i32.photobucket.com/albums/d22/Galdri/005-4.jpg
The hight of the tire is about 18 inches:
http://i32.photobucket.com/albums/d22/Galdri/002-1.jpg
The rim would have been about 5+ inches
http://i32.photobucket.com/albums/d22/Galdri/003-3.jpg
I truly do not know what this is from.
Thanks for that Bograt.
I´ll pop down to the hangar later to take a picture to post on here.
Thank you guys.
I´m having some doubts about it being from a Beau, as the tire has a very strange profile. It is VERY thin across, but with rather high sidewalls (if you can call it that).
I´ll pop down to the airport today and take a picture. A picture will explain a lot better than words how strange this thing looks!
Are you sure the date of the picture is March 1942??
The nearest I can get is October 1942 for a loss like that :confused:
Having met “THE MAN” at Jet2 a few years ago, it will not be a merger, that is for SURE :eek::D:D For the few minutes I met him he didn´t seem like the “merger” kind of guy, but rather like keep it all guy! I think he will go down with Jet2, rather than merge! If we talk about Jet2 TAKING OVER, some other airline, I´ll believe it, but not a merger. So, IMHO, it will be a take over, NOT a merger, of what ever airline is P.M. sights.
And as a final note, PPRUNE are just horrible for that kind as a gossip! Or any kind of discussion for that matter!! 😮
Flying Heritage has already published the final paint after careful research. It will wear the same non-standard field applied paint that it had went it went down.
Just as it should! Why find some “fancy” colour scheme when the original aircraft (THIS ONE) had out of the ordernary scheme that looks great??
Whilst it may be the last one extant, having regard to the level of appeal that post-war Miles aeroplanes seem to have at present
AA, I´m not sure I follow you there! The appeal of post-war Miles types is as strong now as it has ever been. Quite a few of them have changed hands in the last few years, both as flying aircraft and as restoration projects. Problem is, there is not a lot of them left and as a resault, the market seems stagnated. In the last 4 years (approximately) we have had AFAIK, 4 Geminis (2 flying, 2 projects) and 2 Messengers (one flying another “almost” flying) change hands. In my opinion, that speaks volumes for the appeal of post-war Miles types. Someone is actually prepared to buy, when the owner wants to sell! The price, on the other hand, is not always out in the public.
in the context of the current asking price and the economic climate that might explain why it has not aroused any particular interest from prospective purchasers.
The aircraft in question has been up for sale for many years, way before the current “economic climate” and in all that time, has failed to find a buyer. Lets just say, the price tag is only part of the problem! It has aroused interest for sure, and a guy I know that is an avid collector of all things Miles, had a look but walked away.
Regards,
S
That is really good news :D:D
Graham,
Thank you for starting this tread! I learned something new from it!
I would, however, like to make a small observation. This was a test flight for a new wing modification of the DC-8 and after reading the test “report” (it was made for public consumption!) I would not classify the -8 as an SST! In the report there are some subtle hints about this being much more problematic than if the report is taken at face value.
First of all would be the recovery. The aircraft was trimmed nose up BEFORE the dive, so a steady 50 pound push would be required to maintain the dive angle. Even with that amount of nose up trim, the pilots were unable to pull out from the dive with a pull up force in excess of 100 pounds. So with the trim set to initially to a position requiring a push of 50 pounds to maintain the dive, and the a pull of over 100 pounds to try to recover with out resaults, seems a bit far fetched to be able to call the -8 a “reliable”, every pilot´s SST.
A second, and maybe more troubling observation, is the fact that when they were recovering at lower altitudes the aircraft experienced both rudder and aileron flutter! Flutter tendency reduces with altitude. They started the dive at 50.000 feet, got rudder/aileron flutter at 42.000 feet that disappeared as the aircraft decelerated to .94 through 36.000 feet. Given that normal commercial -8´s were “generally” operated not much higher than 35 – 36.000 feet, I can only assume that a dive from that kind of altitudes would have torn the aircraft to shreds due to flutter.
After highlighting the above problems, where does that leave us with regards to supersonic flight on the -8? In my opinion, it will clearly show the aircraft as a transonic aircraft. Yes, it went to Mach 1 and beyond during MANUFACTURERS testing, in controlled conditions (very high!) and in these controlled conditions it exhibited behavior that would have been leathal in normal operations.
As has been highlighted by others above, many other manufactures did high Mach number tests in their aircraft at the time. Without having checked, I would not be very surprised if you could find similar reports of the Boeing Dash 80 (later to be the 707) being put through it´s paces at or near Mach 1.
A supersonic aircraft in my opinion is an aircraft that can, in normal conditions, with average pilot skill, accelerate to Mach 1 in level flight and then be decelerated to transonic speed without undue hassle. I´am afraid the -8 ticks none of these boxes!
Interesting thread though! Some, otherwise useless, time was used to think:eek: