Pilot discretion in climb/airspeed
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Pilot discretion in climb/airspeed
Being used to all sorts of aircraft passing overhead for years, it's apparent that modern aircraft climb at a far higher rate than aircraft in the 70s which must have been struggling to get above 1000 ft/min at times 
Anyway - taking a hypothetical flight from say Edinburgh to London with a moderate weight - typically I would have thought between 3 and 6 thousand ft/min as a normal climb rate based on what I have seen: however, when mooching around the likes of radar virtuel, I have seen some quite unbelievable rates of climb sometimes above 7000 ft/min.
Anyway, assuming an aircraft is cleared to it's cruising height on takeoff, this raises a few questions:
First: as long as it's safe, is there anything to stop the pilot holding a maximum rate climb to cruising altitiude?
Second: Assuming a higher climb rate means less 'airspeed' - the aircraft will have covered less miles 'toward' it's destination as it climbs to altitude (say 200 kts vs 300kts climb) - but does the fact that altitude is reached more quickly generally cancel out the 'slower' initial part of the flight?
Third: for a shortish flight as per above, does getting as high so quickly save any siginificant fuel (assuming that the engine power is the same for climb regardless of rate of climb/forward speed)?
Anyway - taking a hypothetical flight from say Edinburgh to London with a moderate weight - typically I would have thought between 3 and 6 thousand ft/min as a normal climb rate based on what I have seen: however, when mooching around the likes of radar virtuel, I have seen some quite unbelievable rates of climb sometimes above 7000 ft/min.
Anyway, assuming an aircraft is cleared to it's cruising height on takeoff, this raises a few questions:
First: as long as it's safe, is there anything to stop the pilot holding a maximum rate climb to cruising altitiude?
Second: Assuming a higher climb rate means less 'airspeed' - the aircraft will have covered less miles 'toward' it's destination as it climbs to altitude (say 200 kts vs 300kts climb) - but does the fact that altitude is reached more quickly generally cancel out the 'slower' initial part of the flight?
Third: for a shortish flight as per above, does getting as high so quickly save any siginificant fuel (assuming that the engine power is the same for climb regardless of rate of climb/forward speed)?
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First, second, third - No. If you have been 'watching' traffic out of LGW, often a 'good rate' enables ATC to get the a./c above other traffic and turn the a/c northbound earlier than a 'normal' climb rate. Use of 'stick lift' ie trading IAS for climb performance can often produce some startling rates, and if you can turn early does in fact 'save fuel' - to add a caveat on 'third'.
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First - Depending what you fly legislation limits us to 8,000 fpm. 
Second - In deference to BOAC, if you can climb at a good rate to 'get in' a decent tailwind then there may be possible savings on time and fuel. Of course, the opposite is true of a headwind.
Third - What BOAC said. Although a second caveat is that 'expedited' climbs (and descents) can be used to avoid potential collisions with infinite gain!
Second - In deference to BOAC, if you can climb at a good rate to 'get in' a decent tailwind then there may be possible savings on time and fuel. Of course, the opposite is true of a headwind.
Third - What BOAC said. Although a second caveat is that 'expedited' climbs (and descents) can be used to avoid potential collisions with infinite gain!
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Cheers Guys
I actually by chance looked at a trace on planefinder which showed an altitude of 25000 feet over Glasgow for a plane which had left Edinburgh - I assumed it had departed to the east and had therefore gained a few thousand feet on the turn onto a westerly track but the radar trace said otherwise - a westerly departure. my very basic estimate would have put it at around 18000 feet (if not below) at that point purely based on what I normally see. (probably wrong, but then again looking at Aircraft which get a turn to the south earlier (over Penicuik and Peebles) - for the same distance they are considerably lower.
This in turn makes me think of something else: I have only seen this once (from near the airport) - a USA flight took off easterlt and made the turn to NW VERY rapidly after takeoff - it appears most aircraft performing this route climb significantly faster (6 or 7 thousand feet by the north side of the Forth) - illusory due to the turn, or do some routes demand a slightly higher initial climb?
I actually by chance looked at a trace on planefinder which showed an altitude of 25000 feet over Glasgow for a plane which had left Edinburgh - I assumed it had departed to the east and had therefore gained a few thousand feet on the turn onto a westerly track but the radar trace said otherwise - a westerly departure. my very basic estimate would have put it at around 18000 feet (if not below) at that point purely based on what I normally see. (probably wrong, but then again looking at Aircraft which get a turn to the south earlier (over Penicuik and Peebles) - for the same distance they are considerably lower.
This in turn makes me think of something else: I have only seen this once (from near the airport) - a USA flight took off easterlt and made the turn to NW VERY rapidly after takeoff - it appears most aircraft performing this route climb significantly faster (6 or 7 thousand feet by the north side of the Forth) - illusory due to the turn, or do some routes demand a slightly higher initial climb?
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Cheers Guys
I actually by chance looked at a trace on planefinder which showed an altitude of 25000 feet over Glasgow for a plane which had left Edinburgh - I assumed it had departed to the east and had therefore gained a few thousand feet on the turn onto a westerly track but the radar trace said otherwise - a westerly departure. my very basic estimate would have put it at around 18000 feet (if not below) at that point purely based on what I normally see. (probably wrong, but then again looking at Aircraft which get a turn to the south earlier (over Penicuik and Peebles) - for the same distance they are considerably lower.
This in turn makes me think of something else: I have only seen this once (from near the airport) - a USA flight took off easterlt and made the turn to NW VERY rapidly after takeoff - it appears most aircraft performing this route climb significantly faster (6 or 7 thousand feet by the north side of the Forth) - illusory due to the turn, or do some routes demand a slightly higher initial climb?
I actually by chance looked at a trace on planefinder which showed an altitude of 25000 feet over Glasgow for a plane which had left Edinburgh - I assumed it had departed to the east and had therefore gained a few thousand feet on the turn onto a westerly track but the radar trace said otherwise - a westerly departure. my very basic estimate would have put it at around 18000 feet (if not below) at that point purely based on what I normally see. (probably wrong, but then again looking at Aircraft which get a turn to the south earlier (over Penicuik and Peebles) - for the same distance they are considerably lower.
This in turn makes me think of something else: I have only seen this once (from near the airport) - a USA flight took off easterlt and made the turn to NW VERY rapidly after takeoff - it appears most aircraft performing this route climb significantly faster (6 or 7 thousand feet by the north side of the Forth) - illusory due to the turn, or do some routes demand a slightly higher initial climb?
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Leaving EDI for LHR you are, as you say, headed towards GLA.
It is a constant debate as to "what" trigger is required to enable ATC to turn you S. One line of thought is it is altitude i.e. it is worth climbing at, say 210K to get up, rather than a normal climb profile (250K to 10K' then ~300K).
Invariably climb at a set power setting, so RoC down to power/weight ratio, speed schedule (as above). Twins by design have high P:W hence higher RoCs than years gone by...
NoD
It is a constant debate as to "what" trigger is required to enable ATC to turn you S. One line of thought is it is altitude i.e. it is worth climbing at, say 210K to get up, rather than a normal climb profile (250K to 10K' then ~300K).
Invariably climb at a set power setting, so RoC down to power/weight ratio, speed schedule (as above). Twins by design have high P:W hence higher RoCs than years gone by...
NoD
