Humans always try to humanize the spiritual, hence the artist renditions of angels (spiritual-Beings) looking like humans with wings.
The sixth trumpet is the second of the final three woes:
Revelation 8, 9:1-16
8:1 And when he had opened the seventh seal, there was silence in heaven about the space of half an hour.
8:2 And I saw the seven angels which stood before God; and to them were given seven trumpets.
8:3 And another angel came and stood at the altar, having a golden censer; and there was given unto him much incense, that he should offer [it] with the prayers of all the holy people upon the golden altar which was before the Throne.
8:4 And the smoke of the incense, [which came] with the prayers of the holy people, ascended up before God out of the angel's hand.
8:5 And the angel took the censer, and filled it with fire of the altar, and cast [it] unto the Earth: and there were voices, and thunderings, and lightnings, and an earthquake.
8:6 And the seven angels which had the seven trumpets prepared themselves to sound.
8:7 The first angel sounded, and there followed hail and fire mingled with blood, and they were cast upon the Earth: and the third part of trees was burnt up, and all green grass was burnt up.
8:8 And the second angel sounded, and as it were a great "mountain" burning with fire was cast into the sea: and the third part of the sea became blood;
8:9 And the third part of the creatures which were in the sea, and had life, died; and the third part of the ships were destroyed.
8:10 And the third angel sounded, and there fell a great star from heaven, burning as it were a lamp, and it fell upon the third part of the rivers, and upon the fountains of waters;
8:11 And the name of the star is called Wormwood: and the third part of the waters became wormwood; and many men died of the waters, because they were made bitter.
8:12 And the fourth angel sounded, and the third part of the "sun" was smitten, and the third part of the "moon", and the third part of the "stars"; so as the third part of them was darkened, and the "sun" shone not for a third part of it, and the "moon" likewise.
8:13 And I beheld, and heard an angel flying through the midst of heaven, saying with a loud voice, Woe, woe, woe, to the inhabiters of the earth by reason of the other voices of the trumpet of the three angels, which are yet to sound!
9:1 And the fifth angel sounded, and I saw a "Star" (beam/ Being of Light) fall from heaven unto the Earth: and to HIM was given the key of the Bottomless Pit.
9:2 And he opened the Bottomless Pit; and there arose smoke out of the Pit, like the smoke of a great furnace; and the sun and the air were darkened because of the smoke of the pit.
9:3 And there came out of the smoke (something like) locusts upon the Earth: and unto them was given power, like the scorpions of the Earth have power.
9:4 And it was commanded them that they should not hurt the grass of the Earth, neither any green thing, neither any tree; but only those men which have not the seal of God in their foreheads.
9:5 And to them it was given that they should not kill them, but that they should be tormented five months: and their torment [was] as the torment of a scorpion, when he striketh a man.
9:6 And in those days shall men seek death, and shall not find it; and shall desire to die, and death shall flee from them.
9:7 And the shapes of the "locusts" [were] like unto horses prepared unto battle; and on their heads [were] as it were crowns like gold, and their faces [were] as the faces of men.
9:8 And they had hair as the hair of women, and their teeth were as [the teeth] of lions.
9:9 And they had breastplates, as it were breastplates of iron; and the sound of their wings [was] as the sound of chariots of many horses running to battle.
9:10 And they had tails like unto scorpions, and there were stings in their tails: and their power [was] to hurt men five months.
9:11 And they had a king over them, [which is] the angel of the Bottomless Pit, whose name in Hebrew [is] Abaddon (Destroyer), but in Greek [his] name is Apollyon (Destroyer - Satan).
9:12 One woe is past; [and], behold, there come two woes more hereafter.
9:13 And the sixth angel sounded
, and I heard a voice from the four horns of the golden altar which is before God,
9:14 Saying to the sixth angel which had the trumpet, Loose the four angels which are bound
in the great River Euphrates (Turkey, Syria, Iraq and Iran).
9:15 And the four angels were loosed, which were prepared for The Hour, and The Day, (the month, and the year) for to slay the third part of men.
9:16 And the number of the army of the horsemen [were] two hundred thousand thousand (China and Russia): and I HEARD the number of them.
Revelation 16:12 And the sixth angel poured out his vial upon the great River Euphrates; and the "water" thereof was dried up, that the way of the kings of the East (eastern block) might be prepared.
Please see:The Invasion of Kuwait in Prophecy
, for a detailed explanation of these last three woes.