You are right that graph shows that with 11000kg payload the radius of the F-111 is around 350nm or around 700km
sukhoi claims the Su-24 has a radius Operational radius of action at sea level in mixed mode (Vcr in the 200-km area, V=900 km/h in other areas) with PTB external fuel tanks and 6x FAB -500M-62 bombs, km 615
Armament Up to four nuclear bombs on four pivoting wing pylons, and two in internal weapons bay. Wing pylons carry total external load of 25,000 pounds (11,250 kilograms) of bombs, rockets, missiles, or fuel tanks.
By: franc
- 10th June 2008 at 15:34Permalink- Edited 1st January 1970 at 01:00
Experience from having looked at several flight manuals, several aircraft types, several flight regimes. A pair of large subsonic fuel tanks gives you another 10 to 15% of drag in pure subsonic and about 15 to 25% in transonic (start M0.8) regime.
ok, if you guys want calculate sth, let's count it
I am getting serious doubt on your willingness to understand, even though Sens now has arrived at very basic level.
F-111:
NTOW is 37.6t
OEW is 21.6t
Internal fuel is given with 5040 gallons, makes 5040*3.8*0.8 = 15.3t fuel.
That gives a useful payload of 700kg (=2x B61 nuclear bomb).
Aircraft is clean.
Fuel fraction is .41 (that is close to a B747)
Su-24:
NTOW is 38t
OEW is 22.3t
Internal fuel is 11.1t
Add 2x2000kg and you have 15.1t.
Useful payload is 600kg, or two nuclear bombs.
Fuel fraction is .4.
Aircraft is not clean (~+20-30% drag)
SFC +25% (conservative)
Fuel Flow = SFC * Glide Ratio * Weight
Now, we assume for the F-111:
SFC = 1 (fictional value)*
Glide Ratio = 1/10 (fictional value)
Avg Weight = 29.6t
Fuel Flow: 3.0t/h
In case of the Su-24:
SFC = 1.25
Glide Ratio = 1/8 (20% more drag)
Avg Weight = 30.2t
Fuel Flow: 4.7t/h (50% more than F-111)
the fuel consumption of engine Su-24 fitted only 12% higher than which F-111 fitted. if you defined SFC of F-111 as 100% then SFC of Su-24 will be 1.12, where the 1.25 comes?
if 20% more drag, according to the definition here Glide Ratio of Su-24 should be smaller than F-111, but 1/8 is a fraction much bigger than 1/10. I think its totally converse.
then the weight, where did 30.2t of Su-24 come and where did the 29.6t of F-111 come?
By: franc
- 10th June 2008 at 15:42Permalink- Edited 1st January 1970 at 01:00
You are right that graph shows that with 11000kg payload the radius of the F-111 is around 350nm or around 700km
sukhoi claims the Su-24 has a radius Operational radius of action at sea level in mixed mode (Vcr in the 200-km area, V=900 km/h in other areas) with PTB external fuel tanks and 6x FAB -500M-62 bombs, km 615
Armament Up to four nuclear bombs on four pivoting wing pylons, and two in internal weapons bay. Wing pylons carry total external load of 25,000 pounds (11,250 kilograms) of bombs, rockets, missiles, or fuel tanks.
yes, “see the data shows the F-111 is not very different it might have a better radius but not a big difference” you finally admitted what I have pointed out.
At last.......
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By: MiG-23MLD
- 10th June 2008 at 15:59Permalink- Edited 1st January 1970 at 01:00
yes, “see the data shows the F-111 is not very different it might have a better radius but not a big difference” you finally admitted what I have pointed out.
At last.......
I do agree with you but i would be little bit careful about over stating the difference. 650km is in a Su-24 like this
while the F-111 will fly like this when has 700km radius
the real difference should be like 1230km range for the Su-24 with fuel tanks and bombs and 1550km with fuel tanks and bombs for the FB-111
By: franc
- 10th June 2008 at 16:19Permalink- Edited 1st January 1970 at 01:00
This is your personal view, MiG, picture say sthing, but won't say all of thing completely.
Theoretically, F-111 can load weapon on 4 pylons each wing, but have you EVER seen it fly?;)
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By: MiG-23MLD
- 10th June 2008 at 16:22Permalink- Edited 1st January 1970 at 01:00
This is your personal view, MiG, picture say sthing, but won't say all of thing completely.
I agree with you what i mean simply witha SFC of only 12% at the most the range should be quit comparable, i do agree with you more now, the Su-24 with same loads and fuel carried will be very comparable to the F-111, the difference in in ferry range is only due to more fuel tanks
By: Sens
- 10th June 2008 at 16:26Permalink- Edited 1st January 1970 at 01:00
the real difference should be like 1230km range for the Su-24 with fuel tanks and bombs and 1550km with fuel tanks and bombs for the FB-111
"Operational radius of action at sea level in mixed mode (Vcr in the 200-km area, V=900 km/h in other areas) with PTB external fuel tanks and 6x FAB -500M-62 bombs, km 615"
615 km is 332 nm with 3 tons or 6600 lb of bomb and two 3000 litre PTB.
The same value is how many km or nm with 3 tons or 6600 lb of bomb on internal fuel only?
Just two pivoting wing-stations filled to around 60% capacity each.
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By: MiG-23MLD
- 10th June 2008 at 16:33Permalink- Edited 1st January 1970 at 01:00
"Operational radius of action at sea level in mixed mode (Vcr in the 200-km area, V=900 km/h in other areas) with PTB external fuel tanks and 6x FAB -500M-62 bombs, km 615"
615 km is 332 nm with 3 tons or 6600 lb of bomb and two 3000 litre PTB.
The same value is how many km or nm with 3 tons or 6600 lb of bomb on internal fuel only?
Just two pivoting wing-stations filled to around 60% capacity each.
It will be less of course but the F-111 will have something like 680km range but you forget it carries more internal fuel, the SFC matters true but not to say the difference is as you claimed 30%, the FB-111 with fuel tanks and weapons will have a range of 1580km and the Su-24 of around 1230km, the difference reflects more internal fuel and a slight 10% more economical SFC.
By: Sens
- 10th June 2008 at 19:01Permalink- Edited 1st January 1970 at 01:00
It will be less of course but the F-111 will have something like 680km range but you forget it carries more internal fuel, the SFC matters true but not to say the difference is as you claimed 30%, the FB-111 with fuel tanks and weapons will have a range of 1580km and the Su-24 of around 1230km, the difference reflects more internal fuel and a slight 10% more economical SFC.
Under similar condition (3 tons bomb-load) the AR is at 900 nm for the F-111compared to 332 nm for the Su-24.
That is a difference well over 100% to stay polite.
By: franc
- 10th June 2008 at 21:02Permalink- Edited 1st January 1970 at 01:00
With at least 3 tons load in full payload on Fencer and Aardvark to both, condition will be not compareable.
More than 3 tons warload means only two 3000liter(about 2400kg) each external fuel tanks carried by Su-24 but F-111 can carry four 2271liter(about 1800kg) each external fuel tanks.
Don't forget when F-111 loading 4 1800kg external fuel, and loading more than 3000kg bombs under outboard pylons simultaneously, its wing haveto be fixed.
Even thus, compare with approxi 15ton internal fuel, 4X1800kg=7200kg external fuel could enlarge the range of Aardvark from 4000km to 5600km (I count it as 4000+4000*40% should be reasonable because external fuel added only less than 50% to internal fuel, futhermore considering drag and weight influencing), whereas internal fuel plus 2*2400kg=4800kg external fuel for Su-24 gives 3600km range.
So 3600km/5600km still is go far away from 332nm/900nm you given. As we've said the gap wouln't as bigger as somebody imaged or say wished.
Put in other words, 3 tons warload will enlarge the gap of range between F-111 and Su-24 from 10%(tanks loaded already for Su-24)~30%(without external tank to both) to 36%(2000/5600), but no matter how do you count, the range of Su-24 won't be only 1/3 of F-111.
By: Schorsch
- 10th June 2008 at 22:13Permalink- Edited 1st January 1970 at 01:00
the fuel consumption of engine Su-24 fitted only 12% higher than which F-111 fitted. if you defined SFC of F-111 as 100% then SFC of Su-24 will be 1.12, where the 1.25 comes?
Read my post where I showed turbojet SFC versus turbofan SFC. Don't get trapped by static data, they tell you nothing. For cruise conditions the TJ's SFC is about 20 to 40% higher.
if 20% more drag, according to the definition here Glide Ratio of Su-24 should be smaller than F-111, but 1/8 is a fraction much bigger than 1/10. I think its totally converse.
Glide ratio of a clean fighter aircraft is between 8 and 12 (cruise conditions; before transonic drag rise). Moderate external stores decrease it by roughly 20%. You won't find such information on Wikipedia as it is not public domain knowledge, however, if you take the raw data (plenty available on the net) and analyze it, you arrive at the numbers I gave.
1/10 is inverse glide ratio and means that for for 10t of lift you get 1t of drag. A glide ratio of 5 means 2t of drag for 10t of lift. Not that difficult.
ithen the weight, where did 30.2t of Su-24 come and where did the 29.6t of F-111 come?
OEW + 0.5 * (Payload plus (Fuel-300kg)) + 300kg.
300kg are very military reserves, actually a very low value (any military pilot of either aircraft landing with less than 1t of fuel remaining is in trouble by his superiors).
More detailed figures on OEW, internal fuel and payload may alter the results, but the yardstick is set and you haven't shown anything that really moved it.
(MiG-23MLD's posts are ignored by me). I gave my sources, which are the probably not the best, but on the other hand not the worst or most biased you can get.
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By: star49
- 10th June 2008 at 22:44Permalink- Edited 1st January 1970 at 01:00
Under similar condition (3 tons bomb-load) the AR is at 900 nm for the F-111compared to 332 nm for the Su-24.
That is a difference well over 100% to stay polite.
By: Sens
- 10th June 2008 at 22:52Permalink- Edited 1st January 1970 at 01:00
With at least 3 tons load in full payload on Fencer and Aardvark to both, condition will be not compareable.
More than 3 tons warload means only two 3000liter(about 2400kg) each external fuel tanks carried by Su-24 but F-111 can carry four 2271liter(about 1800kg) each external fuel tanks.
Don't forget when F-111 loading 4 1800kg external fuel, and loading more than 3000kg bombs under outboard pylons simultaneously, its wing haveto be fixed.
Even thus, compare with approxi 15ton internal fuel, 4X1800kg=7200kg external fuel could enlarge the range of Aardvark from 4000km to 5600km (I count it as 4000+4000*40% should be reasonable because external fuel added only less than 50% to internal fuel, futhermore considering drag and weight influencing), whereas internal fuel plus 2*2400kg=4800kg external fuel for Su-24 gives 3600km range.
So 3600km/5600km still is go far away from 332nm/900nm you given. As we've said the gap wouln't as bigger as somebody imaged or say wished.
Put in other words, 3 tons warload will enlarge the gap of range between F-111 and Su-24 from 10%(tanks loaded already for Su-24)~30%(without external tank to both) to 36%(2000/5600), but no matter how do you count, the range of Su-24 won't be only 1/3 of F-111.
Sukhoi gives away: Ferry flight range with 2xPTB-3000 external fuel tanks, km:
- with PTB external fuel tanks dropped 2,775
That is a high-up profile with no weapons.
That max possible range range without air-refuelling.
Stay at low level with Tj and a modest weapon-load that range do drop to 45 % of that high-up profile.
2775 km 45% of that is ~1250 km, which does does correspondent with the data of Sukhoi:
Operational radius of action at sea level in mixed mode (Vcr in the 200-km area, V=900 km/h in other areas) with PTB external fuel tanks and 6x FAB -500M-62 bombs, km 615
The ferry flights range data for the F-111 are high up profile too, without weapon-load.
At low level the F-111 can bring its advantages of Tf in play really, because the range do drop to 55-60% only related to load-conditions, when compared to high-up profile. With the same weapons-load a F-111 can go ~2500 km.
By: Sens
- 10th June 2008 at 23:02Permalink- Edited 1st January 1970 at 01:00
900nm at sea level?
See my response to franc about that.
You can figure it out there.
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By: star49
- 10th June 2008 at 23:06Permalink- Edited 1st January 1970 at 01:00
See my response to franc about that.
You can figure it out there.
with one inflight refuelling range is increased to 5000KM. how possible to increase from 2775KM to 5000KM when there is extra 5000KG fuel in drop tanks to achieve 2775KM.
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By: MiG-23MLD
- 10th June 2008 at 23:32Permalink- Edited 1st January 1970 at 01:00
Under similar condition (3 tons bomb-load) the AR is at 900 nm for the F-111compared to 332 nm for the Su-24.
That is a difference well over 100% to stay polite.
There is a difference in internal fuel you are not accounting for, already the F-111 carries more fuel internally. in any configuration always the F-111 carries more fuel.
In fact at max take off it carries 30 tons of fuel against 22 tons, in fact in reality the SU-24 always will carry 15000kg of fuel not 22000kgs since always carries three fuel tanks, there is always at least 8000kg unacounted for if you want a really realistic comparation for the range you will always need a heavier wepons load in the F-111, not 3000kg of bombs, but more, your polites does not prove the SFC is higher just the F-111 carries more fuel, since the Su-24 is carrying close to 55% of its 8000kg payload capacity and almost 90% of its fuel capacity, you will need in the F-111 to carry more weapons but no external fuel, in fact the F-111 will need to carry the same amount of fuel, already at 6000kg the F-111 with a slight advantage in fuel to upset the difference in weapons has a range 700nm or 1400km not very different from the Su-24 in similar conditions
Conclusion true the F-111 carries more fuel when it carries the same amount of weapons at longer ranges, but the SFC is always around 10% higher for the AL-21 versus the TF-30, this is already a drawback of the Su-24 however the Russians always had 2.4 Su-24s available for each F-111 increasing the odds of an attack and the Su-24 has inflight refuelling
By: Sens
- 10th June 2008 at 23:44Permalink- Edited 1st January 1970 at 01:00
with one inflight refuelling range is increased to 5000KM. how possible to increase from 2775KM to 5000KM when there is extra 5000KG fuel in drop tanks to achieve 2775KM.
Maximum internal fuel, kg 11,100 + [6000 litre *0,78 (specific weight)] 4680 kg =
15780 kg fuel in total = 2775 km, but we assume that the Su-24 is not flown till empty after 2775 km and two tons are left as reserve, when landing.
Practical use for 2775 km will be ~13780 kg or 5 kg per km including the fuel-consuming start and climb-out leg to be on the safe side. (AB usage!)
We keep in mind the air-refuel will be at medium height at least, so the fuel-consuming start and climb-out phase can be ignored here. The Su-24 is hooked to the tanker for ~15 minutes [In-flight refuelling system
Maximum flow rate (at entry pressure of 3.5 kg/cm 2), l/min 1,100]
, the last leg will be ~2000 km left to reach 5000 km in total. So you are in need of less than 10000 kg to top your internal fuel only. When the PTs are not dropped it can be over 14 tons in total, but Sukhoi claims, that the PTs are dropped to free the Su-24 from the drag, when dropped to the end of the first hour into the ferry flight of >6 hours in total or 5000 km.
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By: MiG-23MLD
- 10th June 2008 at 23:57Permalink- Edited 1st January 1970 at 01:00
Maximum internal fuel, kg 11,100 + [6000 litre *0,78 (specific weight)] 4680 kg =
15780 kg fuel in total = 2775 km, but we assume that the Su-24 is not flown till empty after 2775 km and two tons are left as reserve, when landing.
Practical use for 2775 km will be ~13780 kg or 5 kg per km including the fuel-consuming start and climb-out leg to be on the safe side. (AB usage!)
We keep in mind the air-refuel will be at medium height at least, so the fuel-consuming start and climb-out phase can be ignored here. The Su-24 is hooked to the tanker for ~15 minutes [In-flight refuelling system
Maximum flow rate (at entry pressure of 3.5 kg/cm 2), l/min 1,100]
, the last leg will be ~2000 km left to reach 5000 km in total. So you are in need of less than 10000 kg to top your internal fuel only. When the PTs are not dropped it can be over 14 tons in total, but Sukhoi claims, that the PTs are dropped to free the Su-24 from the drag, when dropped to the end of the first hour into the ferry flight of >6 hours in total or 5000 km.
You are wrong the Su-24 achieves the range of 2775km with two tanks not three, see Sukhoi`s webpage it says two fuel tanks that is not 15000kgs but much less, with three fuel tanks it will achieve 3000km, the F-111 when it flies more than 5000km (3165miles) is carrying six fuel tanks twice the number of the Su-24 can carry and more internal fuel, see the max take off given by the Royal Australian air force is 51000kg see this fact
Why the White Paper paradigm is centred upon the F-111 is simple - it carries 34,000 lb of internal fuel, thus making it a frugal consumer of aerial refuelling resources inside a 1,000 NMI radius of Australian continental runways.
already the internal fuel of the F-111 surpasses the fuel capacity of the Su-24 and 1000mn is well within the range of 2775km ferry range for the Su-24
in fact the F-111 carries 19112 liters of internal fuel alone
Combat radius was 1330 miles, with ferry range being 3165 miles with maximum external fuel being carried. Internal fuel capacity was 5043 US gallons. With underwing fuel tanks, a maximum of 7443 US gallons of fuel could be carried
while the Su-224 carries that amount with three fuel tanks
Общая эксплуатационная емкость внутренних баков составляет 11860 литров (у самолетов до N 8-11 с неувеличенным 1-м баком - 11200 литров). Запас топлива может быть увеличен с помощью двух подкрыльевых подвесных баков емкостью по 3000 литров (ПТБ-3000) и одного подфюзеляжного подвесного бака емкостью 2000 литров (ПТБ-2000). При подвеске трех баков суммарный запас топлива доводится до 19860 л.
The overall operational fuel capacity is 11860 litres with internal fuel tanks ( the planes before 8-11 series aircraft with no Enlarged 1 - m tank - had a mx internal fuel capacity of 11200 litres). Fuel can be increased by means of two external fuel tanks with capacity of 3000 litres (PTB-3000) and one ventral suspended tank capacity of 2000 litres (PTB-2000). In total suspension of three fuel tanks brought to 19860 litres.
so if the Su-24 carries 19860 liters and the relation fuel kg is 0.75:1 you get a total fuel capacity of only 14895 kg since Топливо
внутренние топливо, кг 9800
внутренние топливо, л 13000
where in kg the total internal fuel is 9800kg and in liters is 13000
In fact at max fuel the F-111A carries a max of 28281 liters in internal and external tanks or almost more than 8000 liters that the 19860 liters carried by the Su-24 in internal and external fuel tanks or slightly more than 1/3 of extra fuel, in fact if you calculate the relation fuel range the relation is like this 5000km/3000km=1.6 and 28000liters/19000liters= 1.4, you find the SFC of the AL-21 is just slightly higher than that of the TF-30
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By: Jon James - 10th June 2008 at 15:20 Permalink - Edited 1st January 1970 at 01:00
Quick question: Whats the 'PACRIM' JSF on the chart? I take it PACRIM is pacific fleet? Is the F-35C? :confused: and curious.
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By: MiG-23MLD - 10th June 2008 at 15:24 Permalink - Edited 1st January 1970 at 01:00
You are right that graph shows that with 11000kg payload the radius of the F-111 is around 350nm or around 700km
sukhoi claims the Su-24 has a radius
Operational radius of action at sea level in mixed mode (Vcr in the 200-km area, V=900 km/h in other areas) with PTB external fuel tanks and 6x FAB -500M-62 bombs, km 615
http://www.sukhoi.org/eng/planes/military/su24mk/lth/
http://www.ausairpower.net/F-111-Payload-Radius-GD.gif
see the data shows the F-111 is not very different it might have a better radius but not a big difference
Armament Up to four nuclear bombs on four pivoting wing pylons, and two in internal weapons bay. Wing pylons carry total external load of 25,000 pounds (11,250 kilograms) of bombs, rockets, missiles, or fuel tanks.
http://www.fas.org/man/dod-101/sys/ac/f-111.htm
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By: franc - 10th June 2008 at 15:34 Permalink - Edited 1st January 1970 at 01:00
ok, if you guys want calculate sth, let's count itthe fuel consumption of engine Su-24 fitted only 12% higher than which F-111 fitted. if you defined SFC of F-111 as 100% then SFC of Su-24 will be 1.12, where the 1.25 comes?
if 20% more drag, according to the definition here Glide Ratio of Su-24 should be smaller than F-111, but 1/8 is a fraction much bigger than 1/10. I think its totally converse.
then the weight, where did 30.2t of Su-24 come and where did the 29.6t of F-111 come?
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By: franc - 10th June 2008 at 15:42 Permalink - Edited 1st January 1970 at 01:00
yes, “see the data shows the F-111 is not very different it might have a better radius but not a big difference” you finally admitted what I have pointed out.
At last.......
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By: MiG-23MLD - 10th June 2008 at 15:59 Permalink - Edited 1st January 1970 at 01:00
I do agree with you but i would be little bit careful about over stating the difference. 650km is in a Su-24 like this
while the F-111 will fly like this when has 700km radius
the real difference should be like 1230km range for the Su-24 with fuel tanks and bombs and 1550km with fuel tanks and bombs for the FB-111
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By: franc - 10th June 2008 at 16:19 Permalink - Edited 1st January 1970 at 01:00
This is your personal view, MiG, picture say sthing, but won't say all of thing completely.
Theoretically, F-111 can load weapon on 4 pylons each wing, but have you EVER seen it fly?;)
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By: MiG-23MLD - 10th June 2008 at 16:22 Permalink - Edited 1st January 1970 at 01:00
I agree with you what i mean simply witha SFC of only 12% at the most the range should be quit comparable, i do agree with you more now, the Su-24 with same loads and fuel carried will be very comparable to the F-111, the difference in in ferry range is only due to more fuel tanks
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By: Sens - 10th June 2008 at 16:26 Permalink - Edited 1st January 1970 at 01:00
"Operational radius of action at sea level in mixed mode (Vcr in the 200-km area, V=900 km/h in other areas) with PTB external fuel tanks and 6x FAB -500M-62 bombs, km 615"
615 km is 332 nm with 3 tons or 6600 lb of bomb and two 3000 litre PTB.
The same value is how many km or nm with 3 tons or 6600 lb of bomb on internal fuel only?
Just two pivoting wing-stations filled to around 60% capacity each.
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By: MiG-23MLD - 10th June 2008 at 16:33 Permalink - Edited 1st January 1970 at 01:00
It will be less of course but the F-111 will have something like 680km range but you forget it carries more internal fuel, the SFC matters true but not to say the difference is as you claimed 30%, the FB-111 with fuel tanks and weapons will have a range of 1580km and the Su-24 of around 1230km, the difference reflects more internal fuel and a slight 10% more economical SFC.
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By: Sens - 10th June 2008 at 19:01 Permalink - Edited 1st January 1970 at 01:00
Under similar condition (3 tons bomb-load) the AR is at 900 nm for the F-111compared to 332 nm for the Su-24.
That is a difference well over 100% to stay polite.
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By: franc - 10th June 2008 at 21:02 Permalink - Edited 1st January 1970 at 01:00
With at least 3 tons load in full payload on Fencer and Aardvark to both, condition will be not compareable.
More than 3 tons warload means only two 3000liter(about 2400kg) each external fuel tanks carried by Su-24 but F-111 can carry four 2271liter(about 1800kg) each external fuel tanks.
Don't forget when F-111 loading 4 1800kg external fuel, and loading more than 3000kg bombs under outboard pylons simultaneously, its wing haveto be fixed.
Even thus, compare with approxi 15ton internal fuel, 4X1800kg=7200kg external fuel could enlarge the range of Aardvark from 4000km to 5600km (I count it as 4000+4000*40% should be reasonable because external fuel added only less than 50% to internal fuel, futhermore considering drag and weight influencing), whereas internal fuel plus 2*2400kg=4800kg external fuel for Su-24 gives 3600km range.
So 3600km/5600km still is go far away from 332nm/900nm you given. As we've said the gap wouln't as bigger as somebody imaged or say wished.
Put in other words, 3 tons warload will enlarge the gap of range between F-111 and Su-24 from 10%(tanks loaded already for Su-24)~30%(without external tank to both) to 36%(2000/5600), but no matter how do you count, the range of Su-24 won't be only 1/3 of F-111.
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By: Sens - 10th June 2008 at 21:10 Permalink - Edited 1st January 1970 at 01:00
When ETs are empty, they are dropped in a combat mission. So nothing is fixed any longer.
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By: Schorsch - 10th June 2008 at 22:13 Permalink - Edited 1st January 1970 at 01:00
Read my post where I showed turbojet SFC versus turbofan SFC. Don't get trapped by static data, they tell you nothing. For cruise conditions the TJ's SFC is about 20 to 40% higher.
Glide ratio of a clean fighter aircraft is between 8 and 12 (cruise conditions; before transonic drag rise). Moderate external stores decrease it by roughly 20%. You won't find such information on Wikipedia as it is not public domain knowledge, however, if you take the raw data (plenty available on the net) and analyze it, you arrive at the numbers I gave.
1/10 is inverse glide ratio and means that for for 10t of lift you get 1t of drag. A glide ratio of 5 means 2t of drag for 10t of lift. Not that difficult.
OEW + 0.5 * (Payload plus (Fuel-300kg)) + 300kg.
300kg are very military reserves, actually a very low value (any military pilot of either aircraft landing with less than 1t of fuel remaining is in trouble by his superiors).
More detailed figures on OEW, internal fuel and payload may alter the results, but the yardstick is set and you haven't shown anything that really moved it.
(MiG-23MLD's posts are ignored by me). I gave my sources, which are the probably not the best, but on the other hand not the worst or most biased you can get.
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By: star49 - 10th June 2008 at 22:44 Permalink - Edited 1st January 1970 at 01:00
900nm at sea level?
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By: Sens - 10th June 2008 at 22:52 Permalink - Edited 1st January 1970 at 01:00
Sukhoi gives away:
Ferry flight range with 2xPTB-3000 external fuel tanks, km:
- with PTB external fuel tanks dropped 2,775
That is a high-up profile with no weapons.
That max possible range range without air-refuelling.
Stay at low level with Tj and a modest weapon-load that range do drop to 45 % of that high-up profile.
2775 km 45% of that is ~1250 km, which does does correspondent with the data of Sukhoi:
Operational radius of action at sea level in mixed mode (Vcr in the 200-km area, V=900 km/h in other areas) with PTB external fuel tanks and 6x FAB -500M-62 bombs, km 615
The ferry flights range data for the F-111 are high up profile too, without weapon-load.
At low level the F-111 can bring its advantages of Tf in play really, because the range do drop to 55-60% only related to load-conditions, when compared to high-up profile. With the same weapons-load a F-111 can go ~2500 km.
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By: Sens - 10th June 2008 at 23:02 Permalink - Edited 1st January 1970 at 01:00
See my response to franc about that.
You can figure it out there.
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By: star49 - 10th June 2008 at 23:06 Permalink - Edited 1st January 1970 at 01:00
with one inflight refuelling range is increased to 5000KM. how possible to increase from 2775KM to 5000KM when there is extra 5000KG fuel in drop tanks to achieve 2775KM.
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By: MiG-23MLD - 10th June 2008 at 23:32 Permalink - Edited 1st January 1970 at 01:00
There is a difference in internal fuel you are not accounting for, already the F-111 carries more fuel internally. in any configuration always the F-111 carries more fuel.
In fact at max take off it carries 30 tons of fuel against 22 tons, in fact in reality the SU-24 always will carry 15000kg of fuel not 22000kgs since always carries three fuel tanks, there is always at least 8000kg unacounted for if you want a really realistic comparation for the range you will always need a heavier wepons load in the F-111, not 3000kg of bombs, but more, your polites does not prove the SFC is higher just the F-111 carries more fuel, since the Su-24 is carrying close to 55% of its 8000kg payload capacity and almost 90% of its fuel capacity, you will need in the F-111 to carry more weapons but no external fuel, in fact the F-111 will need to carry the same amount of fuel, already at 6000kg the F-111 with a slight advantage in fuel to upset the difference in weapons has a range 700nm or 1400km not very different from the Su-24 in similar conditions
Conclusion true the F-111 carries more fuel when it carries the same amount of weapons at longer ranges, but the SFC is always around 10% higher for the AL-21 versus the TF-30, this is already a drawback of the Su-24 however the Russians always had 2.4 Su-24s available for each F-111 increasing the odds of an attack and the Su-24 has inflight refuelling
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By: Sens - 10th June 2008 at 23:44 Permalink - Edited 1st January 1970 at 01:00
Maximum internal fuel, kg 11,100 + [6000 litre *0,78 (specific weight)] 4680 kg =
15780 kg fuel in total = 2775 km, but we assume that the Su-24 is not flown till empty after 2775 km and two tons are left as reserve, when landing.
Practical use for 2775 km will be ~13780 kg or 5 kg per km including the fuel-consuming start and climb-out leg to be on the safe side. (AB usage!)
We keep in mind the air-refuel will be at medium height at least, so the fuel-consuming start and climb-out phase can be ignored here. The Su-24 is hooked to the tanker for ~15 minutes [In-flight refuelling system
Maximum flow rate (at entry pressure of 3.5 kg/cm 2), l/min 1,100]
, the last leg will be ~2000 km left to reach 5000 km in total. So you are in need of less than 10000 kg to top your internal fuel only. When the PTs are not dropped it can be over 14 tons in total, but Sukhoi claims, that the PTs are dropped to free the Su-24 from the drag, when dropped to the end of the first hour into the ferry flight of >6 hours in total or 5000 km.
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By: MiG-23MLD - 10th June 2008 at 23:57 Permalink - Edited 1st January 1970 at 01:00
You are wrong the Su-24 achieves the range of 2775km with two tanks not three, see Sukhoi`s webpage it says two fuel tanks that is not 15000kgs but much less, with three fuel tanks it will achieve 3000km, the F-111 when it flies more than 5000km (3165miles) is carrying six fuel tanks twice the number of the Su-24 can carry and more internal fuel, see the max take off given by the Royal Australian air force is 51000kg see this fact
Why the White Paper paradigm is centred upon the F-111 is simple - it carries 34,000 lb of internal fuel, thus making it a frugal consumer of aerial refuelling resources inside a 1,000 NMI radius of Australian continental runways.
http://www.ausairpower.net/DT-F-111-Update-Feb-03.html
already the internal fuel of the F-111 surpasses the fuel capacity of the Su-24 and 1000mn is well within the range of 2775km ferry range for the Su-24
in fact the F-111 carries 19112 liters of internal fuel alone
Combat radius was 1330 miles, with ferry range being 3165 miles with maximum external fuel being carried. Internal fuel capacity was 5043 US gallons. With underwing fuel tanks, a maximum of 7443 US gallons of fuel could be carried
http://home.att.net/~jbaugher1/f111_1.html
while the Su-224 carries that amount with three fuel tanks
Общая эксплуатационная емкость внутренних баков составляет 11860 литров (у самолетов до N 8-11 с неувеличенным 1-м баком - 11200 литров). Запас топлива может быть увеличен с помощью двух подкрыльевых подвесных баков емкостью по 3000 литров (ПТБ-3000) и одного подфюзеляжного подвесного бака емкостью 2000 литров (ПТБ-2000). При подвеске трех баков суммарный запас топлива доводится до 19860 л.
The overall operational fuel capacity is 11860 litres with internal fuel tanks ( the planes before 8-11 series aircraft with no Enlarged 1 - m tank - had a mx internal fuel capacity of 11200 litres). Fuel can be increased by means of two external fuel tanks with capacity of 3000 litres (PTB-3000) and one ventral suspended tank capacity of 2000 litres (PTB-2000). In total suspension of three fuel tanks brought to 19860 litres.
so if the Su-24 carries 19860 liters and the relation fuel kg is 0.75:1 you get a total fuel capacity of only 14895 kg since Топливо
внутренние топливо, кг 9800
внутренние топливо, л 13000
where in kg the total internal fuel is 9800kg and in liters is 13000
sourcehttp://www.airwar.ru/enc/bomber/su24.html
In fact at max fuel the F-111A carries a max of 28281 liters in internal and external tanks or almost more than 8000 liters that the 19860 liters carried by the Su-24 in internal and external fuel tanks or slightly more than 1/3 of extra fuel, in fact if you calculate the relation fuel range the relation is like this 5000km/3000km=1.6 and 28000liters/19000liters= 1.4, you find the SFC of the AL-21 is just slightly higher than that of the TF-30