Sunday, January 13, 2008

Deeply Dippy

I'm going quite for a few days, so expect a reduced level of posting until the end of the week.

With another exam at Gatwick with two hours and 71 awkward questions like:

"An aircraft is flying at MACH 0.84 at FL 330. The static air temperature is -48°C and the headwind component 52 Kt. At 1338 UTC the controller requests the pilot to cross the meridian of 030W at 1500 UTC. Given the distance to go is 570 NM, the reduced MACH will be?"

Maths isn't my strength at the best of times, so I need to do some serious revision before hopefully starting on a multi-engine course the week after.

I'll still be dipping-in an out though but you may have to chat among yourselves for a while!


9 comments:

Michael Child said...

Simon if you are going to start fly around above us at 555 mph wont it be a bit hard to read the banner. It does look to me as though you just convert it to knots take off 52 and convert it back to MACH or am I missing something.

DrMoores said...

"An aircraft is flying at MACH 0.84 at FL 330. The static air temperature is -48°C and the headwind component 52 Kt. At 1338 UTC the controller requests the pilot to cross the meridian of 030W at 1500 UTC. Given the distance to go is 570 NM, the reduced MACH will be?"

Michael in the example:

As MACH speed is temperature dependant, you first need to calculate what the true air speed is at MACH .84 AT FL330 at -48 degrees.

This is roughly 488 knots

Now work out your ground speed to cover 570 NM in 1:22mins which is 417 knots

You are right about the headwind so add 52 knots and this gives you 469 knots.

Now convert that back to a MACH number which gives you the answer . MACH .8

Easy.. ? now for the other 70 questions!

Anonymous said...

Very impressed!

Michael Child said...

Got you Simon heat and speed both kinetic energy (the same thing) I have to admit to never really grasping the physics of heat. Boiled Boyle and all that thanks for bothering to explain many wouldn’t.

Anonymous said...

Good luck Mr. Moores.

My sister I believe has gone through what you are going through. Hers was to be a commercial pilot. Just don't get migraines once in a blue moon because this is the killer.
She still has a connection with flying though

CS

DrMoores said...

Thank you CS. Reading - see link - in the paper that a 19 year-old has passed gives me some hope that there may be just enough life and intelligence left in the old dog to scrabble through!


http://www.dailymail.co.uk/pages/live/articles/news/news.html?in_article_id=507997&in_page_id=1770

Anonymous said...

Best of luck with the exams, Simon.

That photo of the Mosquito, the “wooden wonder”, reminds me of a British lost opportunity. Some years ago, I was reading a book about the aircraft, and the de Havilland engineers had apparently spotted that the lengthy process of curing the glue in its plywood fuselage in chill winters in the UK and Canada could be considerably accelerated. They wound wires round the hull, and passed high frequency radio waves through it.

Nobody, it seemed, quite knew how it worked, simply that it did. When production ceased, the line was dismantled, and that was that.

In 1945, US company, Raytheon, filed patents for what then became the microwave oven!

Oh well, back to the drawing board……

Regards

Ewen Cameron

P.S. - I calculate I drove to work today at about Mach 0.039. But i've no idea how to compensate for temerature

Anonymous said...

Dr Moores 7.58 - I knew that !

Anonymous said...

I think there is no doubt that Cameron has caught the mood of the country with ideas to tackle welfare dependency.

However he has misread peoples' concerns.

People are concerned about benefits systems abusers (and there are loads of them we all know it no matter what the PC Brigade say) BUT

People generally agree with the principle that our society should provide a safety net (benefits and income supplementation) below which none can fall and a ladder up which all could climb.

There are two problems

(1) Those who fiddle the system and end up a lot beter off than those working their socks off on the lower rungs of that ladder

(2) Those who don't need to fiddle the system to be better off than working (such as large families)

What Cameron is proposing is akin to the measures taken to address gun crime or dangerous dogs. Preach to the converted broad sweep legislation.

All Work Test all the people on incapacity benefits ? How long would that take ? 5 years with the appeal process brought to a cringing overload halt in the first month ?

Artifical work for the unemployed. 600,000 people. How many public sector supervisors would need to be recruited ? 100,000 more public sector parasites ?

All that Cameron is proposing is the equivalent of a General reinforcing a weak position. All that happens is that more troops end up in a weak position.

The original postwar benefits system needs to be ripped up and replaced with a reversible tax system. IE Move to a strong position.