The Latest Clear Pics of J20 and The Way To Calculate The Length

[Mr.Eddie]

(First)：From a Chinese military website “飞扬”
first let's take a look of two clear pics of J20, they are the most clear pics i have ever seen those days.and you can see the date
:"引用 推荐 编辑 只看 复制 Posted: 2010-12-31 14:20 "
the last day of 2010

(Second)the way to calculate the length of j20
the estimated length of j20 is 19.5M-19.8M

there are some details please click link：¼¸ºõÊÇ×ȷµÄJ-20³¤¶È¹ÀË㣨19.5-19.8Ã×£©£¡~~~»¶Ó*¼ì²é¹ÀËã¹ý³Ì£¡ ·ÉÑï¾üÊ ÐñÈÕ³ö¶«·½£¬¾«²ÊÔÚ·ÉÑï - powered by phpwind.net

 

[Hindutvadi]

 

[Hindutvadi]

Isnt the needle kind of thing(dunno what they call it) different in both pics(with trucks)? Are they two prototypes?

 

[azfar]

considering f22's length i-e 18.9m j20's length must be longer then 20m.

 

[topjumper]

(First)：From a Chinese military website “飞扬”
first let's take a look of two clear pics of J20, they are the most clear pics i have ever seen those days.and you can see the date
:"引用 推荐 编辑 只看 复制 Posted: 2010-12-31 14:20 "
the last day of 2010

(Second)the way to calculate the length of j20
the estimated length of j20 is 19.5M-19.8M

there are some details please click link：¼¸ºõÊÇ×ȷµÄJ-20³¤¶È¹ÀË㣨19.5-19.8Ã×£©£¡~~~»¶Ó*¼ì²é¹ÀËã¹ý³Ì£¡ ·ÉÑï¾üÊ ÐñÈÕ³ö¶«·½£¬¾«²ÊÔÚ·ÉÑï - powered by phpwind.net

19.5 ~ 19.8m, that's about the same as what I calculated too. The question is how long really is a J-10? I used 15.5m, but I also heard some people say it's in the range of 16~16.5, but either way I think the J-20 is smaller than the size of a flanker.

 

[sohailbarki]

I dont like its air intakes.they dont look nice at all

Actually i like the intakes of this model

 

[SBD-3]

19.5 ~ 19.8m, that's about the same as what I calculated too. The question is how long really is a J-10? I used 15.5m, but I also heard some people say it's in the range of 16~16.5, but either way I think the J-20 is smaller than the size of a flanker.

IMHO there is a basic flaw with this i.e. the reference pics may not be from same distance, thus leading to confusing results...... here are my calculations. here both the planes are at almost similar distance (at least we may consider our estimates reliability because both airframes would be present at some distance from each other but lets neglect that

now here we can see that J-20 is app 140~145% the size of J-10 since J-10's lenght is app 15.5m thus my estimate of J-20's lenght come at around 21-21.5 meters

 

[scuthan]

IMHO there is a basic flaw with this i.e. the reference pics may not be from same distance, thus leading to confusing results...... here are my calculations. here both the planes are at almost similar distance (at least we may consider our estimates reliability because both airframes would be present at some distance from each other but lets neglect that

now here we can see that J-20 is app 140~145% the size of J-10 since J-10's lenght is app 15.5m thus my estimate of J-20's lenght come at around 21-21.5 meters

the major problem is that j20 is not parallel to j10s in this pic. besides the phototaker didn't stand far enough from the birds. thus it must be smalller than 140%~145%

 

[SBD-3]

the major problem is that j20 is not parallelt to j10s. besides the phototaker didn't stand far enough from the birds.

I agree thats why i revised the max length to 21.5 as hardcore lenght was app 21.8M

 

[naumananjum]

hmm
it must be longer then f 22
i have read some where in j 20 topics
that it is a huge fighter

 

[topjumper]

IMHO there is a basic flaw with this i.e. the reference pics may not be from same distance, thus leading to confusing results...... here are my calculations. here both the planes are at almost similar distance (at least we may consider our estimates reliability because both airframes would be present at some distance from each other but lets neglect that

now here we can see that J-20 is app 140~145% the size of J-10 since J-10's lenght is app 15.5m thus my estimate of J-20's lenght come at around 21-21.5 meters

Hmmm I actually still think the first couple of pics with the trucks are better pics to assess the length.

The biggest assumption we have to make on those truck images are that the observer is so far from the objects of interest so that the distance between the truck and jet is negligible, hence we can assume that they are on the same radius.

If hyperthetically speaking that the truck and plane are on the same radius from the viewer (say r1) in picture 1, and also on the same radius (say r2) in picture 2, then we don't actually require r1 = r2 to be able to compare the size of these two jets.

What can really throw our calculation off is the "depth" between the truck and plane: J-10's wing span is about 10m, and let's say the truck packs about 1 meter away from the wing, then in the first image the truck is about 6 meters away from the j-10; let's say J-20's wing span is about the same as that of a flanker (max IMO), then it's about 15m, assuming the truck is also parked about 1 meter away from the tip of the wing, then it's about 8.5m away from the j-20, this might seem to be a quite big difference between the radiuses that the truck and j-20 are on, but if the observer (the origin of the radius) is very very far away (400~500m), then I think our estimation range is pretty good!

 

[topjumper]

Any ways, does anyone know how long a J-10 is? If we get that wrong then every estimation is off!

 

[Manticore]

this was the pic that i put in one of my jxx videos
http://dc231.*******.com/img/yfpLdElA/0.3666557861182367/2g2.jpghttp://dc231.*******.com/img/UrZIa7AP/0.5154021269757554/2g_online.jpg

 

[jagjitnatt]

(First)：From a Chinese military website “飞扬”
first let's take a look of two clear pics of J20, they are the most clear pics i have ever seen those days.and you can see the date
:"引用 推荐 编辑 只看 复制 Posted: 2010-12-31 14:20 "
the last day of 2010

(Second)the way to calculate the length of j20
the estimated length of j20 is 19.5M-19.8M

there are some details please click link：¼¸ºõÊÇ×ȷµÄJ-20³¤¶È¹ÀË㣨19.5-19.8Ã×£©£¡~~~»¶Ó*¼ì²é¹ÀËã¹ý³Ì£¡ ·ÉÑï¾üÊ ÐñÈÕ³ö¶«·½£¬¾«²ÊÔÚ·ÉÑï - powered by phpwind.net

Your method of calculation seems to be most accurate till now. Good work. Congrats for that.

One thing I wanna mention from ur pics is that the distance between the truck and the aircraft is different in both the pic (J10 and J20).
The distance seems to be more in case of J10, and less in J20.

Another thing is that in one of the pics, the truck is not exactly perpendicular to the camera sight. Its a small degree of difference but it makes 2-5% error in length estimation, since the aircraft is much longer than the truck.

So overall, you can expect an error of around 5-10% depending on variability in the above data. Its very tough to tell for now, but it definitely should be at least 5% small than ur current estimates.

My 2 cents.

 

[scuthan]

One thing I wanna mention from ur pics is that the distance between the truck and the aircraft is different in both the pic (J10 and J20).
The distance seems to be more in case of J10, and less in J20.

if j20 has less distance from the truck, then the length of the j20 will be overestimated.

Another thing is that in one of the pics, the truck is not exactly perpendicular to the camera sight. Its a small degree of difference but it makes 2-5% error in length estimation, since the aircraft is much longer than the truck.

So overall, you can expect an error of around 5-10% depending on variability in the above data. Its very tough to tell for now, but it definitely should be at least 5% small than ur current estimates.

it doesn't matter at all if the truck is perpendicular to the camera sight or not as long as the truck is parallel to the aircrafts.

given there is a angle of 5degree between truck and plane, the variation will be

1 -cos(5)=0.38%

given there is a angle of 10 degree, the variation will be

1 -cos(10)= 1.52%

a man with average parking ability will have less than 5degree variation.