At what speed does VFR become too difficult?
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From: Wildest Surrey
I once took John Farley in G-VTOL from Dunsfold to Bedford on radar; it took about 7 min takeoff to touchdown; on another occasion Duncan Simpson was taking a Hawk to Hatfield (from Dunsfold again) and asked (husky voiced) 'is it OK to do 350 here (Woodley below controlled airspace) or should I slow down'!!
Thread Starter
Fly Conventional Gear
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From: Winchester
Come on, chaps, just calm down!
One is sometimes just left feeling on PPRuNe you simply shouldn't have posted anything in the first place.
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From: Richard Burtonville, South Wales.
At what speed does VFR become too difficult?
CG
Joined: May 1999
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From: Quite near 'An aerodrome somewhere in England'
"Well whatever you call it when ATC advise you are identified, give you a squawk, steer you away from traffic, descend you and steer you for the centreline."
My 'Walter Mitty' caution has just lit up.....
Kid with a scanner?
My 'Walter Mitty' caution has just lit up.....
Kid with a scanner?
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From: Dublin
Good idea, with the radar controller the star perhaps, with TCAS and transponders as support
I know you'll say but what about primiary radar.....I'm getting a radar advisory service, but as I understand it many types don't paint very well on primary radar. Primiary radar also gives no altitude indication. Hence the need to have see and avoid, which has only got a chance if the speeds aren't too great, which is why we have a speed limit.
dp
Joined: Sep 2003
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From: UK,Twighlight Zone
Ah, see your off the floor Bose.
Thanks for your interest Bose but might be best if you save your quips for the good slagging you keep geting on the IMC rating thread.
Thanks for your interest Bose but might be best if you save your quips for the good slagging you keep geting on the IMC rating thread.
To be fair every-time you post I end up on the floor laughing. I may get slagged off but at least I am consistent.....
It does amuse me though how you sink to personal abuse when unable to come back with wit when a bit of humour is aimed at you.
So you going to answer the question then!
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From: heathrow
To be fair every-time you post I end up on the floor laughing. I may get slagged off but at least I am consistent.....
It does amuse me though how you sink to personal abuse when unable to come back with wit when a bit of humour is aimed at you
It does amuse me though how you sink to personal abuse when unable to come back with wit when a bit of humour is aimed at you
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From: Amsterdam
Oh man, I was out flying this afternoon (training aerobatics, 2000' hard deck, 2500' lower limit and BKN033 - good practice) and missed this slugfest. Three pages in, what, four-five hours? Fortunately it's all recorded for posterity.
Anyway,
Don't know if that's exactly true, but I do remember seeing somewhere that airline cockpit windows have to withstand a bird strike (of a certain size/weight bird) up to 250 knots.
Anyway,
Isn't the whole purpose of the 250kt speed limit to allow see and avoid some chance of working?
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From: France
250 below 10 is priincipally about see and avoid, though just why is lost in the mists of time. There are similar certification issues, which are convenient for manufacturers who don't want to fit hugely expensive windows. 
In answer to the original question, why does it matter? Just change to IFR.
In answer to the original question, why does it matter? Just change to IFR.
Joined: May 1999
Aviation Qualifications: ATP+Mil
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From: Quite near 'An aerodrome somewhere in England'
On 16 Dec 1960, a United Airlines DC-8 and a TWA Super Constellation collided in midair over Brooklyn, N.Y., killing all 128 occupants aboard the aircraft and eight persons on the ground. CAB determined that the probable cause was that the United Airlines flight proceeded beyond its clearance limit and confines of the airspace assigned by ATC. The DC-8's high speed, coupled with a change of clearance which reduced the distance which the aircraft needed to travel by approximately 11 miles, contributed to the crash. The Board concluded that the crew did not take note of the change of time and distance associated with the new clearance. The crew's workload was increased by the fact that one of their two VOR receivers was inoperative, a fact unbeknown to ATC.
FAA actions taken as a result of the accident included:
1. A requirement that pilots operating under instrument flight rules report malfunctions of navigation or communications equipment, effective 17 Feb 1961.
2. A programme to equip all turbine-powered aircraft with DME.
3. A speed rule, effective 18 Dec 1961, prohibiting aircraft from exceeding 250 knots when within 30 nautical miles of a destination airport and below 10000 feet, except for certain military jets requiring a higher minimum speed for safe operation.
4. Other steps to strengthen air traffic control procedures.
FAA actions taken as a result of the accident included:
1. A requirement that pilots operating under instrument flight rules report malfunctions of navigation or communications equipment, effective 17 Feb 1961.
2. A programme to equip all turbine-powered aircraft with DME.
3. A speed rule, effective 18 Dec 1961, prohibiting aircraft from exceeding 250 knots when within 30 nautical miles of a destination airport and below 10000 feet, except for certain military jets requiring a higher minimum speed for safe operation.
4. Other steps to strengthen air traffic control procedures.
Last edited by BEagle; 13th January 2008 at 19:37.
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From: EuroGA.org
Contacttower
Let me give you a decent reply then.
"Assuming one is flying around the packed airspace of Southern England "
It is busy only in some places, and mainly below 1500ft or so. In past 10 years, 11 UK mid-airs of which 10 below 1000ft and 1 reportedly at 1800ft.
Few in GA would fly at those levels if going somewhere "fast". Most serious VFR pilots fly as high as they can, clouds and airspace permitting. In the absence of weather/airspace one would fly at 4000+ft as this gives you calm air even on hot summer days. The best MPG (typical IFR tourer, non-turbo engine) is at 7000-10000ft.
"trying to get words in edge ways"
This is the way the PPL is taught (high radio workload, inside leg measurement supplied to every ATC unit within 2,000nm radius) but one doesn't actually do this when flying for real. You can go non-radio in Class G - no point in calling up any ATC enroute unless they can offer you a radar service, and if you get that, and give them your routing (A-B-C-D using navaid waypoints, not village names) they tend to leave you alone, with implicit MATZ transits etc. They are busy enough dealing with pilots who don't know where they are going or are non-transponding so nobody knows how high they are.
" while trying to stay aware of your position with nothing but DR and the map."
Why navigate WW1-style when there is no need to? Get a big moving map GPS, and your nav workload falls by at least 90%.
"At what speed does this simply become too difficult? At 100kts it's possible, but at 250kts say would it still be practical or would it just be a matter of time before you ended up busting airspace?"
I can't speak for dead reckoning (I don't do it) but the RAF seem to get about OK at higher speeds, allegedly with just maps, headings and timing. Mind you, they are the cream of the cream of the young men (those that don't make the grade used to become navigators and end up in the CAA
) and don't compare with civilian pilot recruits at all. They also have good ground backup and - due to generally poor fuel endurance - fly carefully preplanned missions. Some of them do have GPS; in fact any military plane that goes anywhere near any real action needs to have proper nav.
250kt at 3000ft would be a piece of cake, with a GPS - just follow the magenta line, manually or on autopilot. I've seen 220kt ground speed and it wasn't really noticeable; the ground below moves just a little faster than usual. I often wish I had 250kt IAS, to cover distances. Obviously one doesn't fly the circuit at 250kt.
Poor visibility is something else. You can fly legal UK-PPL VFR with 3000m vis, which is more or less total haze ahead. I don't see anybody dead reckoning in that, other than at a very low speed and low level. Very hard work.
Regarding the 250kt limit, this is 250kt IAS. With the TAS multiplier (in a 250kt IAS descent through/from FL100) and some tailwind, your GS could easily be 300-350kt and you would still be legal.
Let me give you a decent reply then.
"Assuming one is flying around the packed airspace of Southern England "
It is busy only in some places, and mainly below 1500ft or so. In past 10 years, 11 UK mid-airs of which 10 below 1000ft and 1 reportedly at 1800ft.
Few in GA would fly at those levels if going somewhere "fast". Most serious VFR pilots fly as high as they can, clouds and airspace permitting. In the absence of weather/airspace one would fly at 4000+ft as this gives you calm air even on hot summer days. The best MPG (typical IFR tourer, non-turbo engine) is at 7000-10000ft.
"trying to get words in edge ways"
This is the way the PPL is taught (high radio workload, inside leg measurement supplied to every ATC unit within 2,000nm radius) but one doesn't actually do this when flying for real. You can go non-radio in Class G - no point in calling up any ATC enroute unless they can offer you a radar service, and if you get that, and give them your routing (A-B-C-D using navaid waypoints, not village names) they tend to leave you alone, with implicit MATZ transits etc. They are busy enough dealing with pilots who don't know where they are going or are non-transponding so nobody knows how high they are.
" while trying to stay aware of your position with nothing but DR and the map."
Why navigate WW1-style when there is no need to? Get a big moving map GPS, and your nav workload falls by at least 90%.
"At what speed does this simply become too difficult? At 100kts it's possible, but at 250kts say would it still be practical or would it just be a matter of time before you ended up busting airspace?"
I can't speak for dead reckoning (I don't do it) but the RAF seem to get about OK at higher speeds, allegedly with just maps, headings and timing. Mind you, they are the cream of the cream of the young men (those that don't make the grade used to become navigators and end up in the CAA
) and don't compare with civilian pilot recruits at all. They also have good ground backup and - due to generally poor fuel endurance - fly carefully preplanned missions. Some of them do have GPS; in fact any military plane that goes anywhere near any real action needs to have proper nav.250kt at 3000ft would be a piece of cake, with a GPS - just follow the magenta line, manually or on autopilot. I've seen 220kt ground speed and it wasn't really noticeable; the ground below moves just a little faster than usual. I often wish I had 250kt IAS, to cover distances. Obviously one doesn't fly the circuit at 250kt.
Poor visibility is something else. You can fly legal UK-PPL VFR with 3000m vis, which is more or less total haze ahead. I don't see anybody dead reckoning in that, other than at a very low speed and low level. Very hard work.
Regarding the 250kt limit, this is 250kt IAS. With the TAS multiplier (in a 250kt IAS descent through/from FL100) and some tailwind, your GS could easily be 300-350kt and you would still be legal.